Extensions and Upgrading from 1.5 to 2

I've been using MMF 1.5 for awhile now and have been working on a project with it, and have been thinking about upgrading to 2. My question is, if I were to move the .cca to MMF2, how compatible would my third-party extensions be? I'm hoping that MMF2 can natively use any MMF 1.5 extensions; if not, I'm using the Direction Calculator, Control X, DirectSound, Layer Object, the RTS Object (only for distance calculations and can be easily replaced), and String Parser 2.

If you copy the objects onto the relevent MMF1.5 extension folder In MMF2 then open your project in MMF2 you can start the long task of migrating your game data/events accross to MMF2. IMO you should finish the game in MMF1.5 then move over to MMF2 for all other projects..

DirectSound hasn't been ported to MMF2, you have to use another object : either the internal sounds, they have more features in MMF2, or a sound object like ONU.

Not sure about the RTS object.

The other objects exist in MMF2.