Okay.  This happened a few days back and I thought it was probably an isolated incident, but it happened again twice today and I am starting to get worried...

I was working on my current project, a simple scifi scene in C8 Pro, and I had to just let it sit for a while so I could have dinner etc.  So I minimized it and left.  A few hours later I restored it from the taskbar and was about to resume work on it.  But...  I immediately noticed that I could no longer access certain commands.  Minor stuff like Save and Save as.  that kind of thing.  I also could not select anything from the sidebar icons.  When I would hover my mouse over them, it changes to an open hand icon and would do nothing.  I closed the program and restarted it and there was no change.  Last time I had to reboot the system to get it working again.  Has anyone else had this problem.  I seem to still be able to save using the Kbd. shortcut but the mouse pointer is totally useless.  About 90% of my menu and icon commands are like this and I can't insert modify or otherwise manipulate any of my scene elements.