Problem opening staad file and misc

Hi,

While opening any staad files (connect edition) in my system I have to try it at least 2 times, sometimes after clicking 4/5 times the file opens. Please help how to solve this. Furthermore, after assigning any load in a wrong position, if undo option is selected then the staad file no longer works (although toggle is an option but please let me know how to fix it). The file needs to be closed and to be opened once again after trying 2/3 times. Please help.

Regards,

Uttam