Hi Larry,
of course, I can't be sure, but we experienced a bug (at least I think it is) with the activity restriction setting. For some activities, LMS won't accept the conditions for (in our case) hiding of activity. In our version of Totara, we still can't use audiences for this option (restrict access), but some other criteria like date we are using at the moment. The solution that worked for us is to double click on the hide/unhide button. I'm a bit embarrassed to write this, but it's true :)
We didn't experience many bugs with Totara, in 99% of cases it was some setting being set inadvertently the wrong way, Can you maybe share a screenshot of that course page? Usually, it shows on the screen the condition which a user needs to satisfy to access/see the activity in question.
Best,
Vlad