Have a look at this screen shot.  After about 10 or 15 iterations of calculations I get this error.  Its been going on for a while now, and I lose everything after it happens.

Is it just me?

please attach your script here so I can recreate the issue. unfortunately, from the picture I can't figure out what's happening.

also please save the script before any computations so this way you make sure you don't loose the entire model when something goes wrong.