Although we have had a few users complain about it, we have been unable to duplicate any apparent slowdowns compared to 7.5 (or even 7.4). So I’m sorry to bother you again, but we really need details - the exact windows you had open. This means which projects, what type of window (notes, SLT, BT Renderings, etc.), and any other tools you may have had open (like Biblical Terms, Wordlist, etc.).
Also, I noticed that the machines don’t have a lot of memory. Paratext 7.6 does use a bit more memory than previous versions. Would you also check to make sure you are not out of memory on the machine (this would mean more than 80% of your maximum being used in Task Manager).