Thanks for that, Eoin! I asked that question because I wanted to make my (forthcoming) "Random select answers" question type, which is based on the OU multiple response.
I have used your All-or-Nothing Multiple Choice question type mobile scripts, with the necessary modifications and am glad to report that things work fine for my own "Random select answers" question type.
I only have a small display bug, which is shared by all "choice" question types (including yours) and which I have mentioned on the Mobile forum at https://moodle.org/mod/forum/discuss.php?d=424928#p1711308
Joseph