FWIW, Campy uses loctite on their chainring bolts from the factory. They can be real tough to break loose the first time.

If you are having problems with loosening, blue loctite won't hurt a thing. As for the tightening thing, is they are all snugged up a little to start with, it's not critical to cross tighten like a wheel, but it won't hirt either. Chain rings are quite flexible in comparison. Putting only one bolt in at a time and tightening each all the way wouldn't be smart.

I apply some light oil to the chainring and spider contact area once in awhile to prevent creaks.