SQL Data Interface

We are interested in using nopCommerce for our retail chain, but I have some questions regarding the data access layer in nopCommerce.

Disregarding any stored procedures in the database, are all of the database calls consolidated to any specific group of files in the source?  It looks like nop.DataAccess or nop.DataAccess.Sql would be the places to look, but I want to make sure that there aren't other calls spread around.

We plan to leverage our existing infrastructure and database structure, and would need to rewrite the access layer to accommodate that.

Is there any existing documentation that goes into any detail that would help?

You should review the source code on CodePlex for version 1.70 (not yet released). nopCommerce has switched to using the Entity Framework for data access making it much more flexible for other database environments.

I'd prefer to stay with a stable release as we hope to get this off the ground within the next 30 days.  Am I right that all of the database access currently happens in those 2 modules?