8:41 p.m. on November 21, 2012 (EST)
It is not necessarily the tent that is the issue. It is a 3 season tent for a reason. The fly is apparently designed for the purpose of ventilation. I recently found myself in a similar situation(somewhat) with a Hilleberg 3 season tent and I spoke in reference to my experience here.
3 season tents are typically(not always) designed to provide great ventilation.
From what I am hearing here the tent is designed to create a chimney effect and maximum airflow with the top vent & elevated fly.
I personally have always purchased tents that have some type of material other than mesh extending above the bathtub floor section of the shelter inner.
Such as shown in the photo below:

This will somewhat alleviate the issue encountered to an extent but it WILL NOT alleviate it 100%.
Direction of pitch can have alot to do with it, so can area of where the shelter is pitched, so on and so forth.
I am not saying direction of pitch will cure the problem but maybe try pitching the vestibules(either/or being I think that model has dual entrance/vestis) facing towards the wind.
Another option would be to try and find an area to pitch where you have some type of wind brake.
There is even another option which would be to pitch the tent in an area where there is some vegetation. This should somewhat cut down on the rebound of the rain splashing up and misting out the inside of the shelter.
....and to be on the safe side carry a few trash can liner bags to put your gear/clothes in at night. They are cheap, light, multi-functional, and can save your tail in a major way.
Hypothermia sucks, I have experienced it. AVOID AT ALL COSTS !!!
The Limelight is not a bad tent at all. I have slept in one on a few occasions over the years in some pretty good driving rains and didn't have much trouble.
Now on the bag.
What is the model of BA bag that you own and what were the temps?
I like the winter/late winter the most out of all the seasons and I am on trail during this time of year the most. I do more solo trekking at night than I do during the day on some trips. The snow, with a clear sky and a bright moon, is priceless...
Anywho(sorry I had a moment.)
I am thinking that it is possible that you may have an inadequate bag for the temps. I have slept many a night on trail where when I woke the opening in my "super powered sleep sack" had a film of ice around it so I am kinda scratching my head on this one.
It is possible that you had inadequate insulation under you. By this I mean some type of pad to keep the cold ground from sucking the heat from you internal combustion chamber.
When you lie in a bag you compress the insulation under you in a major way. While compressing said insulation you also seriously compromise it's ability to insulate you...
(Remember, a bag doesn't provide heat, it just holds in the heat your body generates.)
This is where a pad comes into place.
Were you using one?
If not I strongly suggest you consider it. It makes a ton of difference.
Another suggestion I have is that if you are using the bag outside of the parameters for what it was designed(temp rating,) instead of dropping the dough on a new one consider purchasing a liner.
Numero uno on my short list would be Sea to Summit's Reactor Extreme.
This could possible help ya out as well and will not drain the wallet.
Just a few thoughts. Hope it helps.
-Rick