The calls to draw decals are done from the current active ability in the SpawnTileMarkers function. Static meshes in UE4 can be set to receive decals in their settings under Rendering -> bReceivesDecals.
Hey Asheron, sorry to hear that. This is the right place to report bugs. These issues are news to me. Could you give me some more info? Are you using the latest version of ATBTT and latest version of UE4? Are you using a Windows computer? Could you tell me the precise steps to replicate the issues you are having so I can test it myself? Also, if anyone else following this thread are having the same issues, please let me know.