Hello,
i tried to reproduce the case with different settings. I found out , that this problem occurs when the brushes get very big. When i use the same case with smaller brushes this problem does not occur.
I dont know the exact dimension anymore but i can tell you that it always occured when the cylinder brush was bigger than 20.0 on y axis. It also occurs when i try to cut the cylinder with many small subtractive box brushes. But the problem still occured. So i think ts has something to do with the additive cylinder brush.
Using the actual version of unreal tournament editor.
I just tried the case after the new update. I found out how to reproduce it. I build the brushes like in the pictures above. Then i marked both brushes and hit create static mash. Then this problem occurs (only with big brushes). From this point, the program seems to be buggy too when i just hit build geometry. When i hit build geometry before i create the static mesh the probem does not occur