An auto lift bridge can be a little tricky since the built-in code I use to activate them (as mocrossings) is designed to trigger at the approach of a train - not at the approach of a car or truck. It can be done if the bridge is set up to have boats which are configured as locos running on invisible track in the water. The bridge is normally closed and opens at the approach of the boat (which thinks its a train) and stops the auto traffic.
If your not interested in them being interactive I can easily convert a few from rail to auto for you. Let me know by name and kuid.
Ben
P.S. (almost forgot) I just uploaded a combination 4-lane auto and 1 track lift bridge but it isn't interactive (by request). If your interested its called Forbes River Bridge. Be on the DLS sometime next week (I hope).