I myself don't wanna blame Technic for anything, but I'm afraid the procedure will turn every other mod upside down as only Hexxit appears that way right now. I know it's some kind of code error due to the Intel graphic/Mac/Technic combination. And it only started now, I've been playing the mod - like the other users above - for a while. I didn't update my Java (since other websites/applications got bugged with the newest version), but once again: if it was a plugin problem, all mods would be upside down. Technic clearly updated something on the code of the mod. We just wanna make sure it keeps working wonderfully as it always had.
I'm REALLY afraid the youtube fix solution will turn all the other mods upside down. But as I already deleted, reseted, restarted, reinstalled once, what the hell... I'll do it again if I have to. I'll keep you posted on results.