I just noticed, that the brush-tool behaves weird when I select an area of my map using Hextiles and try to copy it. When I try to copy it to a tile straight beneath the original tile, everything is fine. But when I choose one 0.5x to the left/right (which is every other row the case), the selection messes up like so:
It seems as if the neighbourhood of the hex tiles is not always properly recognized. Same applies for the automap feature.