Thank you very much for your help, that gave me some nice new ideas to have in mind.
To clarify, I don't plan to use multiple compilers, since I'm using only Delphi, so you can assume that all the versions running will be exactly the same. But the processors, no way.
Onto the new questions
Does anyone knows how can I handle this floating point errors on the application?
If I send snapshots of objects, what would they contain? Forces? Heading? Can I set it directly in chipmunk, or should I do something like this:
Given the client's current position
And the desired position received from the server, do:
Calculate force so that current position becomes desired position. Apply.
Something like this?
I could also only send the snapshots that are "in range" of the client (like, distance less than 30 units), an easy optimization to reduce the snapshots.
I'm also considering doing the physics server side, I'm not sure however about the responsiveness client-side, that's something I should experiment to see it working. However, I'm not sure about the dead reckoning (heh, never did something like this, either).
Thank you for your help, and pleased to hear any other idea on this subject.