Thank you but unfortunately it wouldn't solve my problem. It's probably not possible since none of the editors or code I found around the web works with anything smaller than what BrowEdit uses (the "brush" size, texture size per se doesn't matter). Oh well.
On BrowEdit a GAT cell is 1/4 the size of the smallest texture you can insert.
Is it possible to have a texture that matches the size of a single GAT cell? Even if you have to manually edit the maps or code.