So, there are a lot of cool features in 8.4, but one that might bite you(as it bit me) is that there is now an authorization that you have to explicitly use in order to allow users to interact with a task list. I think this is a good thing, but it got me during a demo this am.
It’s under Console → Organization management → Users. If you don’t use it, you might find that your custom task lists don’t work. Also, it’s super-extra tricky because if you’re a more empowered role(like a Developer), I think you’re assumed to have the access to the process: in which case, if you’re testing with your own credentials, you won’t notice that your regular users can’t access their process task lists.
You can read more about it here: Authorizations
As RUN-DMC would say: it’s tricky.
