I write very complex commercial and custom programs for science, engineering, and business, often using FileMaker.  I know that I'm taxing FM's abilities---and it sometimes chokes.  With FileMaker 7, if I click on a tab to go to a different layout, the new layout appears instantly, even though the calculations have just begun.  But in FileMaker 11, if I click on a tab to go to a different layout,  the new layout doesn't appear until the calculations are completed.  However, if the calculations are very complicated, the new layout appears almost entirely white!  Now, sometimes FM will complete its work and display all the fields, as it should; in other cases, FM seems to be churning--Windows says the program is "unresponsive"--and the program does not complete.  (And, no, I  don't code "infinite" loops.)  Has anyone else experienced this?  What, if anything, can be done?

Are all these calculations unstored?  Do they need to be?  I wonder if everything needs to be recalculated just because you switch tabs/layout.

How many Calculation fields are there?

Many. many hundreds of calculation fields, all unstored.  However, I'm going to be building a new dual Xeon 6146 Gold  rig, with ECC memory, so maybe that will clear up the problems.

OK, guys, I finally solved the problem:  I simply set the executable file to compatibility with Windows XP Service Pack 3.  I'm still on Windows 7 Pro 64 (and seriously thinking about moving to Windows 10 Pro 64),  and most of the time FileMaker 32 bit works fine on this OS, but sometimes the 64 bit property makes a difference!  Who the heck knew about this?