My understanding is that DOpus 8's File Collections are meant to be transient, and only are saved upon exit.
That really means if you're adding Files to a Collection, and DOpus crashes, your changes are lost.
I can see why search results collections or duplicate finder collections can be thought of as transient. But, I'd like to see the option to set collections to be "permanent", meaning, if they are set that way they get saved as you add files to them.
I thought about this because I was working on a previously-saved collection, and DOpus crashed, taking with it all my added files. Unfortunately, it killed my saved collections as well...