I can't help with the Loctite question. I don't use it often enough to remember. But I'd advise against it, because you do need to take it apart some time in the future and even the soft stuff will make the task harder.

With enough torque from the appropriate wrench you can get it tight enough that it will not come apart. French and Italian BBs have the same problem. I've got one of each, no, wait, the tandem has two more. So one Italian and three(!) French BBs, and they stay together. You just have to be firm and screw your eyes up funny when you tighten them.