Some stores might not be aware of this trade and pre-order promo, if they are unsure on how to do it, nicely ask them to look-up the weekly 'plays' for directions located within FS internal retail gateway.
To simplify things, the trade 2 for pre-orders promo follows the same procedures as any other game trade-in method.
1. Ensure the two titles of the game is on the futureshop.ca/usedgame website.
2. Process the two games with their repective values into a giftcard.
3. Use the full giftcard amount towards the pre-order (It must be done by 'layaway' to use up the full amount)
4. Customer must keep both receipt, one for trade-in games and one for layaway.
5. come back on release day and pickup the game. (use the layaway and use the house account to zero out remainder of the amount.)
I hope this clarify some things, but don't quote me on this.....only use this as a reference. For associates, full details on the procedure is in the retail 'plays'. (Hopefully, I'm allow to post this....if not, mod please edit it.)
Anyways, It's a new process for trade-in, it's gonna take some time before every store is able to execute this process perfectly. Please give the associate some time to figure this out, playing nice will help us all in the long run. If some stores are still confused, like above poster said....feel free to ask your neighbor store 
