#1
Here are a few measures of the bass/guitar music to make this easier to explain:



If that's not legible, basically it just gives chords and says for the guitar to use the chord symbols as a guide. I have absolutely no idea what in the world this means. For example in measure 22, would I let the G#m7 ring for 2 beats or would I strum it as written? My choir director is being slow in digging up a recording so I am out of luck so far in that respect.

no.
#2
the chords above the lines and the notes in the lines are two diferent things.

you have to play the G#m7 for 2 beats, until the next chord starts. the notes in the lines are for another instrument / voice / whatever. the chords above are just to play along to the melody
Beer is fine.
#4
you can improvise the rhythms of the chords as well so just play it the way you feel fits the piece
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#5
the chord is G#m7 b5 which you can play like this EADGBE:xx6777

do you want to post the voicings you are using for each chord ?
if you find what rhythm the bass and drums are playing you can use that to give you and idea of what to strum or pick and blend in with the song