All right! Here's what to do when having problems with those Child windows in Wine: In your home folder press Ctrl+h to unhide hidden files and directories Enter folder .wine open the file user.reg with any text editor find the section with the window settings which is appropiate - in my case Summasummarum - Kontokort Erase the section - if you are scared just cut and paste it in an empty file Save changes and restart the Windows program, Summasummarum in my case. Voila Window settings are reset.
