Shared Authentication with Microsoft Membership Provider

I am adding nopCommerce to an existing ASP.Net site that uses Microsoft's forms authentication.  

Searching these forums I see that in nopCommerce version 1.x people were sharing the authentication cookie then writing custom code to synchronize the customer data between the two applications.

Is this still the preferred method in version 2.x. Modifying the web.config and changing the source code goes against the wonderful new "plugin" model and makes upgrading more difficult.

Any help would be appreciated. I am new to MVC so if something doesn't already exist could someone recommend a nopCommerce savvy developer.

I am also hoping someone has upgraded the default authorize.net plugin so that recurrence is full automatic similar to the paypal direct plugin.

Questions and comment welcome.

Ok it seems the most common solution is share the authentication cookie. Here is another good link. For you future Googlers the best keyword to use is "single sign-on".

The next problem: How to sync the parent customer data with the nopCommerce database. In the past we replaced the nopCommerce customer table with a view of the parent app's customer data. This worked but makes upgrading nopCommerce difficult.  Any suggestions?

I am still looking for nopCommerce developer recommendations.

Not much support here for single sign-on I have discovered.  Have you ever found an answer for how to implement SSO with nopcommerce?