Rise 360: Quiz Continue button leads to blank screen

Just a few updates on above information:

• Just to confirm, when get blank screen the passing result does not pass back to LMS. i.e. remains Incomplete. Need to re-enter and exit for result to load. (i.e. resume state opens to next lesson). 
• blank screen appears after 2 attempts: both if fail then pass; and if do 2 passes in a row. (i.e. quiz attempt 1 pass, retry button, quiz attempt 2 pass, continue = blank screen).