"Back in August 2011" was just last month, right? Just checking. Anyway, sorry for the bad experience. As a guy who is active with Tiki but not a hardcore PHP coder, I feel your pain. First of all, while Tiki has many developers, not all are active and relatively few are skilled enough and up to date enough with the current code to fix the bugs you're talking about. Then the ones who are, being volunteers as all Tiki devs are, have their own agendas and schedules.
If you have a look at http://sourceforge.net/mailarchive/forum.php?forum_name=tikiwiki-cvs, you can see there's a lot of coding going on, even in the dog days of summer.
Fixing bugs that standard Tiki installations will inevitably encounter should be a top priority, and these are addressed especially just prior to a release, but the code is sprawling and hours are few. I suggest that you join the https://lists.sourceforge.net/lists/listinfo/tikiwiki-devel mailing list and make your point directly to the developers (many of whom don't see these forums very often because, actually, they're busy coding).