It doesn't matter when you take vitamins, etc. Just take them

The easiest way is to just drop the carbs in the morning and in the last meal pre-bed. This will help you sleep better and have ample benefits on serotonin release among other things.

Andy is a personal friend of mine but I cannot comment on those since I know very little about the program.

During training you want free form BCAA. Take two scoops of machine fuel during your workout. 

Test boosters will boost test, but depending on what you are taking, it all depends. Most suck and won't do much. Insurgent and Barracuda will help you reproduce based on data.

ALL OF THEM! See the split in www.dropfactorbook.com

Just throw in a couple WOD's a day with your bodybuilding split! 

Perhaps:

Push

WOD Lower intensive

Off

Pull

WOD Upper Intensive

Legs 

Off 

I see NO benefit to fasted cardio versus cardio in a fed state. I do see it being beneficial to sip on Machine Fuel during cardio if fasted, yes.

It depends on overall intake. If at 1g per pound of bodyweight daily, it doesn't matter when you eat it. But excess will simply be converted to carbs via gluconeogensis. So not a waste, it will just be used for energy.

It should ENHANCE it. Your self confidence and body image should be enhanced.