After encountering more problems, the file was bigger, i tried the following KISS solution (KISS = Keep it simple and stupid):
Removed the program with the maintenance tool completely from the pc, then installed it again, opened the file: every single problem seems now gone. I don't know why this is happening, but it helps, the problems encountered 5 min. ago are gone... You should save your file first, make copies.
So I suppose the structure of the program code has problems with managing the RAM, the CPU, or corruption on supporting, internal files, it seems to save bad state, no refresh, after the while, it seems like "Windows 98", the longer you use it, the worse it gets - so then you had to reinstall Windows. It seems the same thing…
I wanted to share this with you, maybe this provides you some sleepless nights before programming a show
