Generally, double and add 2, and add the skill CS bonus. GM can work to offset based on character emphasis since you would need a 8 to get to 18 in DnD which you could get in DnD to start but not in Incarna. No matter what, a 4 in Incarna is the maximum non-bonus rating in DnD.
CHA = CHA; INT = WIS; STR = STR; RSN = INT; RCT = DEX; SAN = SAN;
PER = If you have a 6+ you get to add 1 to your Perception skill (including passive)
VGR = CON; Incarna adaptations of +1 large, -1 small impact