I have begun some testing of 18_stable (beta) and was trying to test some features so I started by exporting some questions from 1.6+ in the GIFT format and then importing them. In the process, I get a "An error occurred during import processing" - Could not insert quiz answer "true")!
I am attaching a GIFT formatted text file of questions. Of particular concern is that it does add in to the question database the true/false question that it fails on; however, then if I try to preview the question I get an:
Error: Missing question options! and Error: Could not start a new attempt at the quiz message which basically just mucks up the category because there are some unusable questions that cause errors.
To reproduce, attempt to import questions using the attached GIFT text file - or any GIFT with T/F questions.
Let me know if you have any questions or need additional information. Peace.