Changing h264 level

i have not tried compressor but i think i actually fixed my problem, only to run into another one. so i merged the two files back together again using the mp4 box bash in terminal it worked on my computer, but when i stream to the xbox, i get an error code (it is an mp4 by the way). this error meant the file was over 4gb (because it is in hd). so then i used the mkv merge bash in terminal to split up the 8gb mp4 into 8 1gb mp4s. these wont work using quicktime meaning for some reason they are no longer true mp4s, and to reassure that, when trying to stream to the xbox it doesnt work with the error code telling me it is the wrong format. Any ideas?

ive done more google searchs than you could ever imagine, and that website really wont help me, especially since it doesnt even support mac os x. but after much trial and error i figured out that if i open the original mp4 (that is a true mp4) in quicktime i can trim it into under 4gb lengths and save it as different things (video1.mp4, video2.mp4, etc. ) and they are now also true mp4s and play natively on the xbox. so i guess i answered my own question but if someone else ever runs into this same probably hopefully they dont have to do so much searching as i did.

ha yeah i know i hate that 4gb limit. i knew the full hd movie wouldnt play becaue if the limit, i just did it because i needed to see what the exact error code was which told me what the problem was. thanks though.