First of all, you did not encounter a single gamebreaking bug.
Secondly, you´d be amazed what you can upset by tweaking around. There´s a reason why anything tweaked, modded or otherwisely modified isn´t officially supported by the PoP team.
You brought it upon yourself. Either do a fresh and new install and start a new save, or learn to cope with the problems occuring and doing a proper troubleshoot run.
And always backup your files and the attached savegames BEFORE you change anything. If you don´t you can wreck the corrupted save all along the install.
As for your tavern sound problem, apply a search and check the support thread. This problem has occured in the past and solutions have been presented. Also check the files manually wether or not they sound correctly and your machine is able to play them.
Now some explanation:
Prophesy of Pendor started a long time ago for Mount and Blade 1.011 as a project of Saxondragon alone (who´s a veteran in the IT industry and now focus and teaches game development, behold his newest project!).
The result of this ambition was PoP 1.21 which was an amazing mod around at it´s time. Still, it was a one man concept/work and as such limited. However, it attracted quite al ot of attention of silent, genuis, noisy and cantankerous people who became involved.
The team grew and it resulted in PoP 2.62 or something like that, till Warband came out. And with Warband came a cartload of new possibilities.
So rather than porting over, it was redone for Warband mainly under the guidance of the WB lead programmer Mad Vader and Fawzia-dokhtar-i-Sanjar, which ultimately resulted in PoP 3.611.
See the full credit lists if you´re interested in it, either in the stickified threads here or your manual in your game folder.
So while SD is the father or PoP and main developer, the whole thing and present version is the result of quite a lot of people, of a rare and enthusiastic team. Mad Vader coded large parts of it and quite a few things uniquely for PoP and is probably one of the three or five people (check credits and look up the lead coders) actually understanding how the game works and why it´s a certain bad idea to tweak this or that on your own.
And apart from that probably foaming by reading your complainment about "troublesome gamebreaking bugs". At least I would if I was him. Because I´m pretty sure that most of PoP´s real gamebreaking bugs have been discovered long before you ever played this mod and hunted down and became extinct even before we had the opportunity to locate them doing extensive betatesting.
. I'd certainly like to hear how's the progress going on (maybe some percentages) because I've been looking for THE '@' to be announced for over a year now, and I got to say that PoP is ultimately the best mod out there and probably that fact will stay forever 
