Bleeding the system (part 2)
 

Ok, as of my last post i suspected i had air in the system of my s2 which caused what i think was some coolant loss through the breather (have been bleeding her over the past 4 days and replaced the rad cap with a new one).
Now, about 4 weeks back i had an engine flush as my lifters were tapping loudly and then an oil and filter change which cured things nicely.
Since then the motor hasn't been driven much - a couple of 40mile round trips and some short journeys around town - i have started her daily though so that the battery doesn't go flat.
Went to bleed her again today and more air was present before the coolant flowed through evenly.Let the car idle, checked all the hoses which were warm/hot and switched her off.
Then checked the oil cap - which to my surprise was a very nice milk white colour complete with water droplets.The dipstick however was fine - oil still a lovely golden colour with no water evidence and there's no oil in the coolant reservoir.
The weather here in the uk has been very cold, -8 etc, at night over the past week.Would this be sufficient to cause condensation in the filler tube and oil cap or is it looking likely my head gaskets on it's last legs.
I cleaned the cap and took the motor for a nice long run - she pulled well, no overheating (temp was just on the first mark) and no missfire - checked the cap again at home and it was fine.
Has anyone else experienced lots of condensation on the filler cap in winter/cold temps or am i being a bit paranoid?

You say you started it daily to keep the battery from going flat. How long did you let it run for? If it's not 100% up to temp (oil pressure comes down to 1-2 bar warm idle) then you will still have condensation in your oil. After doing this several times, the amount of condensation in your oil can become rather substantial, and on colder days it will settle out on the walls of the oil filler tube, and consequently the oil filler cap. Happens to mine in the winter all the time. I pull the cap bi-weekly to clean the crud off the bottom of it.

Also, it takes quite a while for the battery to charge back up after starting it. It might be a better idea to put a trickle charger on it instead of starting it daily.