Haha oscar, what your writing?
You know very good, that this part was "done" as you left, and that you continued my work and was the last one who wrote on it before you left the team. On of the first things I added to the vmpayment plugin is the selfdisplaying on the frontend.
But to get the paypal plugin working we had to add some important stuff and rewrite some code, thats true. I suggest Dade should take a look on the wiki, the cash on del and the paypal plugin to understand how it is working.