We have our moments when Antetype suddenly force closes (we need more memory) and have high hopes that Antetype recovered our work, but it's not a feature.
A good feature that could be added is the process of saving ever 5-10-whatever minutes automatically. It can be an option that you turn on in preferences, ext.
Is this a good idea?
For this to be useful, you should first fix the problem with the file size that goes only in one direction (up). I've stumbled more than once in files that balloon to hundreds of MBs even if there's almost nothing inside. Tim told me it was a problem in how the OS handles writing files and that you were going to handle that in the future, but seems like it has gone to the back of the line: IMHO this is bread and butter stuff that should be addressed as basic product hygiene.
the file-size problem is still on our list. We started investigating it, but so far we don't have a satisfactory solution to it. (If you could send us such a very big file without much content we would be very happy, and could investigate more what's going on).
Here some workarounds for getting smaller files:
The Force Close seems to be linked to the memory leak issue perhaps. When working in Antetype, if we, say, copy a large amount of items to another screen or area within the current screen, it sometime force closes. This may just be a lack of memory on our side.
As for Autosave, I think how iWorks saving feature works would be an amazing and would really helps us out. It's not something that you would think to add until your computer freezes/shuts down due to no more battery life/ etc.
Thank you for looking into this!