I'm just testing out on my dev machine with Moodle 2.5 before I go into production and there's one last bug to squash. What's happening is this:
Any form (gotten by adding something to a course) that has as a required parameter as a textarea, (1) first loads up normally (2) but just at the end of the loading, it disappears.
I turned on complete dev log and there are no errors or messages given. I tried on different themes and got the same result.