What I would do with the hanging on the projector is buy a celling mount and either attach a I-Beam clamp to the end of the mount or weld it to the end.
Of course, use
safety cable for everything and if you can secure the projector directly into the cable, then I believe that to be safe.
Is the data input into the projector VGA? If so, get a few lengths of 50' or 100' and use a repeater in the middle to boost the signal. Or if VGA cable is too price, then their are VGA to CAT-5 converters so you could run CAT-5 instead of VGA.
If I think on a better way to mount the projector the a I-Beam, I'll pass it along.
Good Luck!