I was going to try it but I do nothave the ferry option on my GPS.

-- Well it works identical to toll and and unpaved avoidances.

Yes but I do not have the ferry check box on my GPS.

I'd like to do a recap on routing options that I have and how they work. Please correct me if I am wrong:

U-turns: done internally by the routing algorithm

-- Well it kinda could be handled by tweezing arcs, but more or less this is useless.

Toll roads: not implemented yet in mkgmap?

-- long ago implemented - you can use add toll=yes.

I'd have to try that.

Highways: by road type

-- what kind of unit to you have to get this working. Never seen any Garmin GPS where one could exclude highways based on type.

I was just assuming here. So you're saying it does not work at the moment?