I am also looking forward to any updates on the module. (in any version of Zen Cart) Naturally, the techs at PayPal can't provide much info on Zen Cart, but they have told me that the Advanced PayPal version puts what you see in the express version inside of an iframe so that the customer does not leave your web site. Apparently, no one has packaged the code for that into a module yet -- I can't find anything on it.