Buy x Get x Free stackable?

[play-a-game]

Do "Buy__, get__free" promotions stack?

I created the following promotions that apply to all my low priced DVDs:

Buy 2, Get 1
Buy 3, Get 2
Buy 4, Get 3

Can anyone confirm only one promotion applies per order? I can't find any info on it.

Thanks!

[sassykzt]

 If you want the promo to be apply only once per order choose the box  the says " One per transaction"  , if you want to allow more ( to stack )  -- so buy 4, get 3 free , and customer buys 8 and gets 6 free,  then choose the one w/o the wording of "one per transaction"

For the buy 4 get 3 -- remind your buyers to put 7 in their cart ( if they buy 8, get 6 -- then they have to put all 14 and so on......in their cart for the promo to be calculated.  Buyers are often confused with this:)  They will purchase 4 and then send you a message of which 3  they want free.  Many buyers do not use their carts.