I've not seen it...but err...the blue paint is made from a dye from the Woad plant, traditionally worn by Picts in battle. The uniform is not authentic, but then the authentic uniform was no clothes...and that would've been an entirely DIFFERENT sort of film
Thus...those two mean little. As for being worse than POTC...that worries me as Pirates wasn't anywhere near as good as people on here make out...Johnny was awesome, other noteable performances, but the plot was just too long and windy for its own good.
As for the spoilers...they're basically all well known...that's the thing...we've all heard that the funeral at the end that Antoine intended was cut and replaced with some sort of wedding thing. Sadly the press don't care so much about spoilers as we do