Hiii guys 
Sorry to request that im new and im trying the new buildings.
Unfortunatly this happen when i try to slice 64x64 with the buildings .
If anyone can help me it would be amaziing

Do you need to slice the buildings?

My advice is to not slice the buildings, use special tile sizes (depending on the buildings size), or better yet in godot don't use buildings as tiles, and use them as sprites.

You need to se Pixels Per Unit to 64, I think is default on 100