Wow, that really should be documented somewhere! I just spent weeks negotiating rates with 2Checkout and switching everything from PayPal over to 2Checkout.
I can't create multiple products as the users purchasing aren't registered yet so there's no way to differentiate them. I also have dozena of codes depending on what magazine, ad, association the user belongs to, etc.
There's no other gateway that supports automatic updating of credit card information for subscriptions. We are losing 50+ accounts a month to expiring cards so this has become critical.
What is the reason this doesn't work? Is it just impossible from the 2Checkout side or is it lack of programming that's been completed on the plugin side? The original user posted about this 4 years ago so I'm guessing the 2Checkout side?