Want to start off saying I'm by no means a strong user, so hard to say what might be causing this, but I've consistently been having the application freeze while working in 2015.  Could be the files I'm working from, we've got stuff that was originally created using AutoCAD lite 98.  Had used Solidworks 2D editor for a while a few years back and got the not responding message quite a bit.  When we changed over to DrafSight were able to plug along for a long time, but when I updated from 2014 to 2015 a few months ago I've been having this happen pretty consistently.  I'm guessing it has to do with files I'm copying parts out of and pasting into the new file, but not sure what I should do about it.  Any help would be appreciated.  I'm on Windows 7 64bit if that matters.

Thanks,

Caleb