Where exactly do you need projection mapping here? If so did you project the texture or did you project the UV? Anyway theres not much need for camera projecting in any of your examples.
Perhaps we should redefine the topic to what your trying to achieve by having to use camera mapping instead.
Camera projection mapping in Maya is not so much documented.
Its not? I dont know about you but i can find how to do this in the manual with 10 seconds of searching.
Anyway yes manuals do not tell you what you can use stuff for. That you have to bring yourself. If they really knew they would have done this stuff instead of you.
for tutorials
Ah ok yes. You know you can not tutorialize everything, Its a pretty inefficient way to do stuff. The world does not work as follows:
do thing 1
do thing 2
you end up with 3
It works as follows:
if you do thing under 1 certain condition and your need is within certain bounds
and then do 2 vbecause of certain things involved in the surroundings
you ned up with 3 most of the time.
For this reason you should not go out and look for recepies and tutorials for yoru problems but rather explanaions of organisation, philosphy, mathematics and so on. Because thats what eduactes you. A list action trains you, but ultimately training is inferior to education. It gets you there this time, and newer any furter. LEarning to think leads you there every time.
PS: You have a pretty bad temporal aliasing on your car in all your clips.