Just had the same thing - but I had quite a lot done. Questions for developers:
1) Why do you consider work in the Script Editor as not being activity and cause a time out
2) Is there an auto save function ie - Save every x minutes - not allowed say it but - like there was in QlikView :-)!
3) If you must program a time out then at least offer save option or a warning - about to time out do you want to save.
Grrrr..... nicely! Lots to redo!