That's not correct - FoxyCart never gets Jamroom's password in any way - the only time you would see this message is if a user had actually created an account with FoxyCart.
If more then one quota is highlighted it will not show up field in quotas. Did not have much time to fully test but from the runs I did, it seems like this is true. At the moment it is not relevant on our site but just mentioning it since came across it.
I'm not sure what you mean by "will not show up field in quotas" - can you clarify that for me?
1) log in as a "normal" user account in a quota that has a 5 song limit.
2) create 5 songs - try to add another and get error
3) delete a song
4) I can now add a song
Try that on your system and let me know if you see an issue.
Like I mentioned in my email response, I don't believe this is caching (I have checked it). I've tested here and it all works as it should for me (I have my cache timer set to 3600).
If you can tell me specifically how to reproduce it (the best you can) I can check it out.