There may have been a glitch with combining potions where the game didn't recognize you had the skill until you opened the skill window again or reloaded the game, or something. Alternately, it may have been working, but placed the restoration potions under another potion or the side menu, making them hard to spot.
Enemy levels are partly dependent on your own level, so if you clear out the BF dungeons and then return to the main game, your opponents should be a little stronger (though I don't think they should go up as many levels as your own characters). I didn't clear any of the BF except to get to the merchants, and the Death Knight Patrols were level 10, as were the listed Citadel Patrols on the trophy page. It is possible the trophy page lists the base level of the creature, and (by design or oversight) does not include the boost based on your character level.
I fought the summoned ghost in the citadel multiple times in order in order to be able to make suggestions for the strategy guide. That fight can be relatively easy or very difficult. If you manage to get the first hit in, interrupt his attack and have the speed and agility to keep hitting him, then it can be an easy fight. If he gets the first hit in, then it can be a difficult fight. Since his level is higher, he tends to attack faster, more frequently and more accurately, so whoever he is attacking can have a difficult time trying to recover and get in many hits of their own (this leaves the other character to do most or all of the damage).
For the cutscene with Samuel, Larian was apparently planning to either have multiple versions of the cutscene depending on your progress, or the rum was going to be a required quest (and the only way to get the key). Somewhere along the way, there was a miscommunication about what was or should be happening with that part of the game.
