you'd just have to provide all external images (textures, backgrounds ...)
I don't think that should be a problem. (Same with .ma files.)
I don't imagine issues between systems and things not being the same in the final renders, though. My understanding that's generally only an issue between processor kinds (Intel vs. MIPS for e.g.). Is this actually the case? What might cause the difference between CPUs in the same processor family?
Depending on how things plan out, it may be convenient to divide rendering shot by shot. Effects shots like the water (splashing &c.) might be the most taxing to do. But maybe these files could be prebaked beforehand before delivery.
Well. Started this project by wondering how I was going to do this. Looked around, and determined I didn't have much personally. I figured hardware rendering could be used here. But if there are folk who are willing to lend their unused CPU cycles for an art project, I think this is a lot more feasible.