Multiple response & HTML5 & Firefox & Storyline2
simple 2 slides with multi response (or multiple choice) graded quiz (default setup). Add a custom "submit" and a custom "next/previous slide" buttons. Export - and review HTML5 version in Firefox browser. Select answers on slide 1 - but DO NOT submit answer, then select "next" and on the next slide select "previous" to go back to slide 1. Now try to change your answers - when you move your mouse over the answers the answers starts shuffling randomly (see attached capture.jpg).
Before you start with "Firefox is not supported" - please be informed that SL1 export works as it should (in same firefox browser). Both SL1&SL2 project files as well as exports are attached.
I searched support forums - it seems you had the same bug in SL1, but it was fixed in update 4.