I recently updated from 1.7 to the newest release and the db conversion failed. So I did a fresh install and have been recreating and updating my surveys. The first one was activated fine and is operational. The second survey will not activate giving the following error

It gives me no useful error. I have no way to debug this. What can I do?

I tried creating a new survey using the copy function. A copy of the already activated survey activates fine. A copy of the non-activating survey also will not activate. So it appears to be a problem with this particular survey.

I went to edit->survey logic file and it detected no syntax errors.
I tried regenerating the question codes, no affect.
I did a db consistancy check and it only found an orphan default value to be deleted and no other problems. Deleting it had no affect.

I'm really reaching here. I see nothing within limesurvey to fix this nor tell what the problem is. The DB is functioning and surveys can still be created and activated, just not this one.

Ok. So I systematically deleted groups and questions, activating in between, to find the offending question. I had one multiple choice question with two subquestions that were identical (both the text and the code). Deleting the duplicate option fixed the problem.

Should not the survey logic check found this?
Should not the activate survey error returned useful information?
Should not the save subquestions function double checked for duplicate or invalid items?
Is this worth a bug report?