I don't know how to fix that directly in the program, but you can reset all the window positions by renaming or deleting the settings file. If you want to try that it is stored in modern Windows versions at:
C:\Users\UserName\AppData\Roaming\MySEQ\positions. xml
UserName is whatever name you use in Windows. The Client program should be closed while you either rename or delete this file.
Edit: I noticed a space right before the file extention. It does not show up in the edit window, so I can't fix it.