Sorry for the late reply, @JBetamaxxx and @Danort. When you make your first post on these forums it takes a while for Epic to validate it and it also seems this prevents me from getting an e-mail notification, so I did not see your comments until now.
The heightmap blueprint is still there, just moved and renamed. You can find it as BP_GA_Platforem in Core/Tiles. You can see an example of implementation in the JungleRaid map.
Yeah, this feature has always been a bit of a headache. For square grids and units up to a size of 5*5 tiles it works fine, but it is the sort of feature that impacts a lot of other features in the toolkit, since it breaks the basic assumtion of 1 tile = one unit. This means that whenever you make an ability or modify the AI you need to write the blueprints so that it targets and considers multiple different tiles etc. In short I would not recommend using big units unless you are very proficient with both blueprints in general and this toolkit in particular. To see an example of an ability set up to work with big units see BP_Ability_Move.
These questions are all related, as all of them have to do with how the toolkit does many things at the start of the game, which does not change unless you do so directly. If you want to add new tile locations after the game has started you need to change the GridLocations TMap in BP_GridManager. To be able to move to that tile, the surrounding tiles must have edges connected to that tile. This is defined in the GridEdges TMap. Since you are talking about platforms I’m assuming you are using multi-level grids, which makes this a bit difficult. However, you can use many of the same function that are used at the beginning of the game to achieve the same effect later. Here is one example setup as a starting point:
First I spawn a BP_GA_Platform actor above the tile hovered over by the mouse (this could just as well have been a regular static mesh):
Next I repeat the setup normally done for the whole grid at the start of the game, but only do it for the index I spawned over as well as all its neighbors (in order to have them connect their edges appropriately):
Here is the pastebin for this code.
This does the job for a platform covering a single tile. For a larger platform, like the one you are suggesting, you would need to loop over every tile the platform covers as well as one more tile in every direction.
Let me know if you run into any difficulties. My next planned tutorials will be about the various grid arrays in BP_GridManager and how they affect pathfinding etc.
Firstly, it only works with square grids, and also does not work 100% with multi-level grids. For single-level square grids it will work, but you need to set both the size of the unit and the max unit size of BP_GridManager. As mentioned before, big units are pretty difficult to work with, and if you are using grids with overlapping levels I would not recommend using this feature.
You are correct that the overwatch ability does not exist in the current version. I broke the implementation during a previous refactoring and have not gotten around to re-implementing it yet. This is partly because I was not perfectly happy with the previous implementation. It is on my list of things to add, but thanks for reminding me about it. Apologies for the incorrect feature listing. I will remove it from the list and will try to add an improved version soon.