How do you lose when your BMR is low?

Actually, it's pretty easy - my BMR is also 1266 (as a 42 year old woman)

Remember that BMR is only the number of calories your body needs just to function, if you were in a coma, you'd need this amount of calorie intake.

I have a home based desk job, so i dont get out much, but just being awake and moving and talking and laughing, i need about 1500 calories to maintain my weight.

Not sure what your activity level is.. but for me, netting 1200 per week guaurantees a weightloss of 1lb per week.

Good luck