Whoa, the GP5 you've made is really good actually! You and your friend surely did a good job.
There were two tabs of Everybody Say Yeah!, but both were those typical (and incomplete) notepad tabs; one for the chords and one for the bass guitar only. In case of your tab, I'm not sure if the notes are all correct, but as I listen to it I assume everything is alright. There were some other things in the tab I found less practical and/or superfluous, though. I'll sum them up below, just to give some feedback.
The first thing is the second synthesizer track. It's completely empty, so I recommend removing it. The first synthesizer track has some text in it (i.e. [organ], [synths]), but additionally, you can just change the instrument at that point. Also, the initial instrument (Fifth Lead) is quite annoying because it adds a fifth on every note, and I'm not sure why you chose that instrument.
The second thing is your use of two voices on a track. Especially with the drums I don't find it handy, simply because you don't have two voices to work with. When you actually could use it well, you only use it for some unimportant notes (referring to the Vocal track). However, I like how you used it in the Guitar I track at bar 74.
Thirdly, the voice track itself is an octave too low. The added octaves (and other lower notes) on the Vocal track are sometimes two octaves too low! I assume you used the keyboard input to write down the vocal part, and then it cannot be helped because the marker for the central c is wrongly placed in Guitar Pro.
Lastly, I'm not really fond of tracks that almost don't add anything useful, like the handclap and the congas. I mean, yes they are there, but who is going to play that anyway? That's just my personal preference, so if you feel it's more complete this way, there's nothing wrong with it, of course.
So yea... my reply became waaaaaaay longer than I imagined, and there even are more things I could point out. Inexhaustible perfectionism... Actually, the notes and rhythms are noted down really well, but at several points I just don't like the way it's written down... in a nutshell.