That sounds confusing. Could you show a picture? It sounds like a better way than how I'm doing the seagulls in MM2CT.It's easy. You create the object in Zmodeler that you want to be the moving object, it must be named correctly and I forget the needed name, but in the latest version of the mm2city toolkit manual (the one that includes simple city) the pathset files and named objects are included. Once you have the object created you can then make the path for it. You just create a flat plane and, depending on the direction you want it to go, add more polies and move them around.
Yes, they are different. As far as the Seagulls go, you really need to do them as dummiesboy has described, because my way requires the track to be a z3d/3ds, not a psdl.DB: No no, your method and Hummers' method seem a lot different. Yours is done through MM2CT while his is done in ZM.
As I mentioned, go download the MM2City Toolkit manual for example pathset files, objects, 3d files, etc. For your own created cities, this is a nice, easy method.