Since you've been on the forums for almost two years now, I assume that you have transitioned to fat-burner. At that point it definitely becomes FAT calories in minus FAT calories out.
If you've hit a plateau, you should probably eat MORE carbohydrates.. perhaps up to 80-100, especially if you're active.
5'0" female, 44 years old. Started Primal October 31, 2011, at a skinny fat 111.5 lbs. Low weight: 99.5 lb on a fast. Gained back to 115(!) on SAD chocolate, potato chips, and stress. Currently keeping food tracker.
I (try to) follow by-the-book primal as advocated by Mark Sisson, except for whey powder and a bit of cream. I advocate a two-month strict adjustment for newbies. But everybody is different and should tweak Primal to their own needs.