I've figured out a workaround, even though there doesn't appear to be a direct solution to my problem. If you're having issues with randomization, it would seem that you have to have a 0 block before your first block with random stimuli. If you try to recall those stimuli later using the ? function (without a block 0), it will not recall the correct stimuli otherwise.

It would be nice if this bug were fixed in an update.