On the main choice page and on the View x responses page, I get either of the following errors:
Fatal error: Unsupported operand types in /Users/aim/Sites/moodle/mod/choice/report.php on line 48
Fatal error: Unsupported operand types in /Users/aim/Sites/moodle/mod/choice/lib.php on line 338
I have had a look at the code, and have found that changing the lines mentioned in the above errors slightly fixes the problem.
Attached are the two diffs containing the fix which I have implemented.