Window Focus - Keep focus on VM application when host is elsewhere

Hi - I'm running Windows 7 on Parallels 12 for Mac in a fullscreen space and never use unity mode. How can I retain focus in my virtual machine applications while using my host OS?

As an example: I run Excel in my VM a lot. To recalculate a workbook properly, the window (lowercase w) must be in focus until Excel is finished calculating. If I switch to the host OS to use Google Chrome while I wait, I lose focus from Excel and the calculation is cancelled.

By activating Spotlight (Cmd+Spacebar) while in the VM is open, I can tell that somehow the active window in Windows loses focus after about 0.5 second. How can I prevent this?

Thanks

 

Hello???

 

Come on you fucks somebody help a brotha out! please!