I have looked after the url-finder-regex and changed some bits. I have just tested the regex on their own and haven't tested them as MyCode. There shouldn't be security-issues with my regex, but maybe there are.
Try to input the followings as MyCode:
(?:[\>\s\(\)]|^)(https?:\/\/[^\/\"\s<>\[\.]+\.(?:[^\/\"\s<>\[\.]+\.)*[\w]+(?::[0-9]+)?(?:\/(?:[^\"\s<>\[]|\[\])*)?(?:[\w\/\)])\.(?:png|jpg|gif|jpeg|bmp))
should be replaced with
<img src="$1" style="width: 100%">
and
(?:[\>\s\(\)]|^)((?:www|ftp)\.(?:[^\/\"\s<>\[\.]+\.)*[\w]+(?::[0-9]+)?(?:\/(?:[^\"\s<\[]|\[\])*)?(?:[\w\/\)])\.(?:png|jpg|gif|jpeg|bmp))
should be replaced with
<img src="//$1" style="width: 100%">
.
I hope that works, I don't have time to debug problems. The Regex itself should work. In the MyCode insert-section in the Admin-CP, there is also an option to controll in which order, the MyCodes are parsed. Maybe you need to tweek there a bit, too.
Best Regards!
Thomas131