I had a quick look at the Fantasy Flight forums and the Rules Reference following on from last night's game to try and clear up a couple of points.
Influence and Agenda Cards: Each Agenda card in your hand is worth 1 Influence. Any thumbs up on the card face, +1 or +2, are in addition to the '1' value of the card, so we were effectively under-scoring ourselves . For example, I had had +2 thumbs up for not having any tiles unexplored, so should have had 3 Influence from that card, not the 2 we counted/thought. Not that any of this would have mattered last night as the tracker should have ended the game several turns earlier! If neither player has the required Influence, nobody wins - it doesn't matter who had the most etc - well, except for bragging rights may be...
Someone on the forum has raised the question about spending a 'dice face' but the answer was very vague and not at all clear - more research/reading the rules is required!
At least we seem to have got the combat sorted though. You can still kill enemies if they are attacking you from an adjacent section. Once you have killed an enemy, a new one of the same type spawns face-down at the nearest matching icon on the tiles - no need to track where they came from.
Shopping: Whenever you are prompted to shop, you first draw a new card into the shop (this will take the shop over the 4 items it should have), take the buy/sell/recruit action and then when resolved, discard any addition shop items to get it back down to 4.