Frequent Compustar Issue

I live in Alaska, I have been installing the new 2W900FM-AS units lately, and the problem I having is when it gets cold such as 0 degrees and below they start acting up. I am having the hardest time figuring out what is wrong. One of the units is installed on a 2002 S10 Pickup and when it is cold, it tries to turn over for less then half a second and then gives up, and since it is in manual mode, it wont let me try again after is fails ( I am not sure if this is normal either) but any way I end up going out there and starting it by key, any ideas?

I have the 12 volt power running out to the battery with 18 guage wire, but the 2 power wires off the brain are tied into it, do you think 18 guage is to small to power it and when it is cold it does not recieve enough power to start the car? Do I need to run a bigger power wire to the brain? Please let me know what you think.

Secondly the same thing is occuring in a 2003 subaru forester, only it doesnt even try and turn over it just sound like the coil comes on then shuts off right away. Then is locks is self in remote start mode until you hold down the button on the remote to shut it off. Any thoughts on this would be great too.