nice render! i could never make a bot like that. Just one thing about the lighting tho, increase the falloff for the lighting. make it squared. That way, it gives some realistic shadowing effects! try it out!
hmm. it was 3 full days of work and u have to puzzle a lot with the pieces. i recommend that u duplicate a lot of parts!
and u should master the tecnique of negative,positive and intersect booleans
tell me if ur finished. if u want i even give u my model to work on