MarketPress payment options

I have my MarketPress plugin installed in a MU WordPress environment. I also have a plugin called menus to restrict access to some menu options.
1.) I would like is there a way that I can restrict menu options in MarketPress?
2.) I have MarketPress installed in Wordpress MU and I have resellers. I would like to know is there a way that I can setup MarketPress to charge a fee each time a reseller has a order (makes a sell).
3.) Is there a way I can have all sites using MarketPress to use the same payment gateway. Example When my resellers make a sell the payment will not go to here paypal account it will go to the Network Administrator Paypal Account and then me as the site administrator will pay each reseller there earns?