1. Enclaves, spawned from the beginning of the game- BS DLC bug, fixed in UF3P
2. Freeze after level-up with OA DLC installed- OA DLC/vanilla bug, partially fixed in UF3P
3. Wrong armor, given to the player after OA DLC simulator- OA bug, fixed in UF3P firstly.
4. You gonna shoot them in the head quest was completed before the time - OA bug, fixed in UF3P firstly.
5. Time of the day did not match with exteriors (night in the morning bug)- fixed in UF3P
6. Charon bug, when hired.
Many others, don't remember already. Full list of fixes can be found in UF3P documentation., not all of them are minor fixes.
That's the thing. UFP does some marvellous work, and greatly improves F3 (as it did for Oblivion) -- the fact it has a few bugs is unfortunate, but I'd rather these were fixed that people staying away from it. UFP for Oblivion is a must-have hands down, and UFP for F3 was shaping up to be the same.
Perhaps we need someome to take over where Quarn and co left off?