Problem fixed
Thanks to Ball000, who showed me a way, to hide a window (and make in reappear again!), no bad hack is necessary any more to hide the main uae window. ChangeWindowShape is my new friend now :). But I still have no idea, how to make a window opened with WA_Visible=FALSE visible again ;). But it does not matter any more.
clusteruk wanted more memory in amigaOS, the next version will have it:
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If you try to give too much memory to amigaOS, you don't get an error message, you just get 0MB of ZIII ram.
Thanks to Ball000, who showed me a way, to hide a window (and make in reappear again!), no bad hack is necessary any more to hide the main uae window. ChangeWindowShape is my new friend now :). But I still have no idea, how to make a window opened with WA_Visible=FALSE visible again ;). But it does not matter any more.
clusteruk wanted more memory in amigaOS, the next version will have it:

If you try to give too much memory to amigaOS, you don't get an error message, you just get 0MB of ZIII ram.