I have the same problem. I have Gravity Forms Version 1.7.9, Gravity Forms + Custom Post Types Version 3.0.1 and Idealien Rideshare Version 0.2.1 plugins. I imported the Rideshare form into Gravity form and added it to a page. When I enter the info into the front end page it creates a Rideshare title in the back end but the rest of the fields are blank. I checked the form and it is using the custom post types. Gravity Forms has the entry when I check on it, but it does not seem to be passing the information to the rideshare back end. I can enter the information through the back end and everything works fine. http://www.morakevents.com/?page_id=169
The latest version – 0.2.2 – resolves this. See http://wordpress.org/plugins/idealien-rideshare/changelog/ for more details.