So what is the phrase?
I thought some people might want to figure it out but I'll reveal next weekend if nobody beats me to it. (Though the names of the images and pdf files is a big hint for some people.)
O pona wawa tawa ante ale. Jan pona o awen musi!
But I haven't looked at the language part.
That is correct. (ni li pona)
Making this a challenge feels a little flat now, so:
Imperative( good (very) toward others (all). People (good), imperative (continue (having fun)).
"Be excellent to each other and party on, dude!"
Be excellent to each other out there.