Nice job!
As for your question at the end, coupons attach to every product listed on them. When a clearinghouse requests inventory records from the store proving they have the sold stock they claim, they ask for all items listed on the coupon.
Therefore, BOGO coupons attach to two products (like a $1.00/2 coupon) and so another manufacturer coupon cannot be used. There may be some stores who say that using both is okay, but because the verbiage on all manufacturer coupons (“one coupon per item purchased”) does not allow this, we do not do it.
For more on BOGO rules, check out our post http://thekrazycouponlady.com/2012/10/08/extreme-couponing-tip-know-this-important-bogo-rule/.