I have a quick question, When starting a new map and in the new map specs
that popup, Is it best to tick RGB Lightmap or leave it blank?

Windows XP SP3
Intel Dual Core CPU: E5200 @ 2.5GHz
4.00GB DDR3 Ram
ASUS P5G41T-M LX
PCIE x16 GeForce GTS 450 1Gb
SB Audigy 4
Spyware Doctor with AntiVirus