Sorry. You were perfectly clear. I was posting without really reading in what category you had posted, and like a noob I didn't even check your profile.
If BB7 is losing a setting like keeping the Hotspot engaged it's either a long standing issue that nobody else has complained about, or there is an issue with your particular BlackBerry. I would suggest upgrading or downgrading the os to another version. Beyond that I'm afraid I have little to offer.