Upgrades Questions

My WPMUDEV Premuim subscription payment just went though this week and I am already hard at work setting up the premium plugins I want to use. I got the upgrades plugin and I have a few questions about it.

1) I don't have a worldpay account, I haven't decided yet whether I even should get one or just only offer paypal. But in the mean time on the credits purchase page is there an easy way to have the worldpay buttons not be added unless its a payment option, such as a not avalible mode? Or would that require modifying the source?

2) I only want to offer upgrades for purchase for 12months to the user, but leave the 1month option for the admin when I am visitng a users upgrades page. Only rarely should an upgrade need to be for 1month, and that is only when I start the subscription for the user. Whats the best way to accomplish this?

3) I have some plugins I want to offer as upgrades that are designed for the plugins directory (Feedburner redirection and Google Analytics for now anyway) and I can't seem to get them to workby moving them unmodified to the upgrade-plugins directory. So what would be easier modifying the plugin to work from upgrade-plugins or writing a script for upgrade-plugins that would activte the necessaey plugin in the plugins directory then deactivate it when it expires, keeping in mind I use plugin commander which comes with plugin activation and deactivation functions I can use to make that part easy. PC would disallow user control over the plugin thats associated with an upgrade and I could even modify my plugins page to even hide them from me so I don't mess anything up by activating or deactivating it there.

Thanks so much.