Best Practices
Discussion about how to use this system

Workflow
You probably work with Tilemaps which are included in a scene rather than Tilemaps loaded from a prefab. 
 This is the easiest way to use TilePlus tiles: just paint and edit them to do what you want. 
 Saved with a Scene 
 When you paint a TPT tile it’s saved with the scene and will be present in a build. 
 
 The TPT tile in the scene is not affected by changes to the asset in the Project folder. 
 The asset in the Project folder is not affected by changes to the tile in the scene. 
 
 If you paint over the TPT tile, it’s deleted from the scene and will no longer be saved. Essentially, the TPT tile becomes like any other Object in the scene. 
 Once you edit the painted TPT tile in-scene you can save it as a new tile asset, drag that into the palette or use a context-menu item to add it to Painter’s Favorites list, and paint it. This is especially useful when prototyping or for creating backups. 
 This is the easiest way to make the most of this new type of tile. Remaining in the scene, you can have references to Scene Objects like GameObjects, Components, etc. in your tile scripts. Once a tile is painted, you can select it with the Palette, edit it in the Tile+Brush Selection Inspector or Tile+Painter, and drag references such as GameObjects into the painted TPT tile fields. Think of it as a Tile promoted to a GameObject, just without a Transform component. That’s close enough for rock and roll. 
 Scene References 
 When a TPT tile is in the Scene, it can have references to other Objects in the Scene. For example, you can have a reference to a GameObject and access its components for scripting, right within the TPT tile’s code if you like. 
 BUT: maybe you want to make prefabs out of Tilemaps and load them while your game is running. 
 If so, you may find this system annoying. There is a limited facility to save Tilemaps as Prefabs as explained in the next section. However, it’s way more efficient to use the TileFab system. Tilefabs allow preserving one or more Tilemaps and any child prefabs into a position-independent archive format. 
 TileFabs are the key technology component underlying the TilePlus layout system, which streams chunks of tiles in and out of the scene as the Camera moves. 
 Tilemaps saved in Prefabs 
 When you create a prefab by dragging a Grid with child Tilemaps to the Project folder, all references to Objects in the Scene are lost just like any other Prefab that you might create. 
 This includes all TPT tiles. If you were to open the Prefab, the locations where TPT tiles had been placed would be replaced with pink or other oddly colored tiles. 
 Because of this, if you mouse-drag a Tilemap or any GameObject that has Tilemaps as child GameObjects into a project folder to create a prefab, and there are any TPT tiles, the system will warn you in the console and will unlink the items you dragged from when you created this prefab so that the scene Tilemaps won’t be corrupted. 
 You may as well delete the prefab that you created as it isn’t useful.

Tilemaps in Prefabs
To make a compatible prefab: 
 
 Select a Grid with child Tilemaps or a single Tilemap, 
 Make a Grid Selection using the Tile Palette or Tile+Painter. 
 
 Then use the Hierarchy window’s TilePlus Bundler context-menu command or the main menu’s Tools/TilePlus/Prefabs/Bundle Tilemaps command. 
 If a Grid or a single Tilemap is selected, then all the tiles and child Prefabs of the Tilemaps are bundled. 
 If a Grid Selection is made, you’ll be prompted to confirm that you want to use the Grid Selection to limit which tiles and Prefabs are bundled. If so, ALL tiles and Prefabs in any Tilemap within the selection are archived. 
 This command archives Tilemap contents into one or more TpTileBundle assets (Bundles, from now on) and optionally creates a special type of prefab. But at this point its use is restricted to simple situations: 
 
 Archive a single selected Tilemap into a Bundle asset along with a TileFab asset. 
 Archive a single selected Grid and its child Tilemaps into multiple Bundle assets along with a TileFab asset, with optional prefab creation. 
 
 To be clear: Compatible prefabs can only comprise a Grid with child Tilemaps and any Prefabs parented to the Tilemaps. If you try to use a multiple selection, or any Grid or Tilemap are in or part of a prefab, then the process will complain and quit. 
 The bundler generally follows this process: 
 
 Is the Grid or Tilemap in a prefab or are you editing in a preview scene? Start again. 
 If the selection was not a grid, you’re asked if you want to continue. No: Start again
 
 If the selection isn’t a grid, then you can’t make a prefab, just archives. 
 
 
 For each tilemap:
 
 Is the Tilemap part of a Prefab? Start again. 
 
 
 Select destination folder. Advice: use a different folder each time!
 
 Is the folder the Assets folder? Start again. 
 
 
 If the selection was a grid, you’re asked if you want to make a Prefab of the Grid and all child Tilemaps (a Tilemap prefab).
 
 If making a Prefab, you’re asked if you want to bundle any Prefabs which are children of the Tilemap GameObjects. 
 
 
 If the selection was a single Tilemap, you’re asked if you want to add any Prefabs which are children of the Tilemap GameObject, and if those should be saved as new Prefabs or Variant Prefabs. 
 
 It’s simpler than that sounds! The choices are presented to you via several dialog boxes and file pickers. 
 With this information, the bundler creates the TpTileBundle assets: one for each Tilemap, then adds all the TPT tiles to the asset. For Unity tiles, it preserves the information in the Tilemap for each tile (color, transform matrix, and flags) as well as a reference to the original Unity tile asset. 
 If you elect to archive prefabs, please note that references to the prefab assets are archived; new copies of the prefabs aren’t created. This means that if you delete one of these prefabs then the reference is null, and the prefab won’t be available when the TpTileBundle asset is used. 
 Note that GameObjects that are instantiated because the Tiles’ GameObject field caused the Tile to instance a GameObject into the scene are not archived. When the TpTileBundle asset is painted (programmatically or via the Tile+Painter) the Tiles re-create the prefab in the scene for you. 
 A TileFab asset is also created in the same folder. This asset has references to all the new TpTileBundle assets and is used with the TpAnimZoneLoader tile or for loading using methods in the TileFabLib library. 
 If you’re making a Tilemap prefab, it’s placed in the folder that you selected earlier. Don’t delete the TileFabs and Bundles created during the bundling process: the Prefab requires them. 
 The created prefab can be used just like any other prefab with one exception: it’s “Locked,” and the TilePlus tile instances are also “Locked.” 
 This locked status is a hint to Tile+Painter and the Tile+Brush to use particular care when it encounters TilePlus tiles in a Prefab. Essentially, you can’t edit this sort of prefab in a Prefab editing context or “Stage” to avoid any chance of corruption, and you can’t edit the TPT tiles or the prefab itself. 
 Regardless of which brush you use, painting, erasing, or any other operation will either revert or just not occur. 
 You’ll also find that you can’t open one of these prefabs in a prefab editing context. Tilemaps with locked tiles display a closed-lock symbol in the hierarchy window. 
 However, you still have the original Grid and/or Tilemaps; unlike normal Prefab creation via Drag and Drop, the source isn’t linked to the created prefab. If you ever need to recreate the original for editing just drag the Prefab into a scene and use the Unity menu command “Prefab/Unpack Completely.” 
 A small component called TpPrefabMarker is added to the Prefab, specifically, to the same GameObject as the Grid. Please don’t remove it UNLESS you unpack the Prefab. If you do unpack, REMOVE the component. If you don’t then it will overwrite all the tiles with tiles from the TileFab whenever your game starts running. At best, a time waster but at worst, you’ll get profoundly confused. Here’s why: 
 When a Prefab is dragged into a scene or instantiated at runtime, PrefabMarker loads the tiles from the TileFab on to the appropriate Tilemaps. This component can be seen at the top-level of the Prefab in the Project folder. 
 You’ll see a reference to the TileFab. While you can change this to a different TileFab, be aware that the unpopulated Tilemaps themselves are in the Prefab and would need to be compatible with whatever TileFab you change to. 
 The BundleLoadFlags field should usually be set to Normal. Use of other settings should be experimental only. 
 It’s important to remember that the Locked Tilemap shouldn’t be edited, moved, picked, flood-filled, etc. 
 The system will actively try to thwart you from doing so, but you can finagle your way around it if you try hard enough. If you do manage to edit a Locked Tilemap somehow and save the prefab overrides, then the prefab can become corrupted and unusable, even if no TPT tiles were modified.

Don't Use Prefabs for Tilemaps
You Probably Don’t Want Tilemap Prefabs 
 They’re not really that useful except in limited circumstances. Each time you drag in a Tilemap prefab, it instantiates an entirely new Grid with Tilemap children. This is true for any Tilemap prefab, even one created normally by dragging a Grid GameObject from a scene to a project folder. 
 What’s more useful is being able to load tiles in groups to existing Tilemaps. You may already do this with Tilemap block move methods and so on. 
 TilePlus’ TileFabs and Bundles handle all this for you and are easy to create. 
 TileFabs and Bundle assets are not Prefabs! 
 Please note that the TileFab and Bundle assets are NOT prefabs: you can’t drag either of these into a scene. 
 However, a TileFab archives the original source Tilemap names and/or tags and the TilePlus library functions for placing them in a scene expects to find these same names and/or tags to place the multiple archived Tilemaps correctly. That is, which Bundle assets referenced by a TileFab should be ‘painted’ on to which Tilemap. It can’t guess. 
 Other Uses for Bundled Tilemaps 
 When using Tile+Painter, Bundle assets and TileFabs appear in the Painting Source (center) column and behave as if they were a single tile: you can paint them onto Tilemaps. 
 This means that you can create chunks of tiles and paint them as if they were a single tile. 
 Bundles : you can paint the entire Bundle or view a list of all the tiles in the Bundle and paint them individually. 
 TileFabs When created from a Grid Selection a TileFab is like a layer cake, with the Tilemaps being the layers. Basically, you can paint N Bundles with one click. 
 TileFabs are also used in the Layout system . 
 For simpler uses, you can add the TpBundleLoader component to any Tilemap’s GameObject. This component loads a single Bundle. Place the component on any compatible Tilemap (same layout, etc.) and drag in the Bundle asset reference. Switch to Play mode and loading will happen automatically if the component’s LoadOnRun toggle is checked. Or you can click the Load button to make a quick test. 
 The Load button is hidden if the Tilemap is part of a Prefab. 
 Similarly, you can add the TpFabLoader component to any Grid’s GameObject. It works in the same fashion as TpBundleLoader. However, it can’t work correctly if the Grid’s child Tilemaps do not match the names and/or tags of the Tilemaps embedded in the TileFab asset. That’s up to you. 
 Finally, you can use a TpBundleTile. This simple tile takes a Bundle reference as a parameter. You can copy it to a Unity Palette or to Painter’s Favorites list and paint it on a Tilemap. When you do, the tile loads the bundle and deletes itself. 
 Bundles and TileFab assets can be used in a running game to dynamically load tiles into Tilemaps using the TpBundleLoader or TpFabLoader components, a TpBundleTile, TpAnimZoneLoader tile, the TpZoneManager, or at the lowest level, the TileFabLib and TpZoneManager libraries. 
 One other note: When you make a prefab or archive, all Scene references are lost as usual. TPT tiles can have Scene references but if your tile doesn’t have any then this doesn’t matter. To be clear, any Scene reference within the same Prefab should work properly.