I have had this issue a while and had hoped the 7.1 update would address these issues but they have not...
Originally I had Windows 8.1 on there and back in Mavericks and VMFusion 6 it worked flawlessly. After the upgrade to Yosemite (I had beta) I've had issues but understandably. Then after 7 came out and Yosemite I thought all would be well... but no. I decided to go back to Windows 7 (for other reasons as well) fresh to see if the issues were maybe around Windows 8.1 but they were not (Side note... this is my Boot Camp partition).
I know there are known issues with iMac 2011's but I have a brand new MBP 2014 that's just a few months old. I tried the workaround using the terminal debug command but it didn't seem to really help. I just took it off and maybe it's slower... I dunno.
I run my VM with 2 cores and 4GB of ram but any programs (IE, Word, Excel, Etc) just run like molasses. Especially if I try to minimize or maximize a window. If I right click on my desktop it takes about 30 seconds for the menu to come up. If I am in an explore window and navigating thru folders looking for files it seems to move just fine.
All in all I need this to work. Is it a VMWare issue? Apple Issue? or what? Can I go to Parallels and it work? (on that note... if I do can I run Parallels using the same boot camp?)
Thanks for any help!