Motion has taken the (unfortunate) step of performing lots of their magic in the MacOSX KERNEL memory-space under the auspices of a kernel process.
When something bad happens – like a memory resource error – not only does Motion crash – but it takes down the whole system.
Whereas, when an app and it’s resources are all located in USER space – then when something bad happens, there’s hope to recover – or, failing that, the app can crash – but NOT the whole system which is what happens with Motion.
This approach they’ve taken is really a sad situation and, unless they get out of KERNEL space and not do all their work in a kernel-process, this kind of nonsense is going to keep being a part of the Motion experience.
FWIW – The times I most often run into trouble are when I have something going on that uses almost all of the system RAM – and that’s not hard to do – or when I am rapidly clicking around from viewing-area to viewing-area and it seems to get behind and lost in the updates.
HTH