in components/com_jevents/libraries/modfunctions.php on line 137, you have used a hardcoded | to split the array. I am using , (comma) to separate the categories so when $catidsin is exploded I only get the first value.
I have simply inserted
$catidsin = str_replace($separator,"|",$catidsin);
before the explode statement and now my module works as it should.