If you are wanting to learn the notes on your fretboard, someone had a thread here with a pointer to a website and video that works very well -- unfortunately, I didn't save it. But it's pretty easy and I'm sure could be adapted to your situation.
Here it is for standard tuning as I remember it:
Because many of us tend to think in patterns, and referencing notes by how close one is to a note we have memorized, we have to break that habit somehow. One way to do that is to learn the fretboard by going circle of 5ths (or was it 4ths?) on each string, but one string at a time until you have that string down.
So let's say you start with the E string in standard tuning. You will play only the first 11 frets plus the open E. Find C. Now move to F. Now Bb.
Because you are finding each note pretty far away from the others, you are actually going to memorize where that note is by itself, rather than in relationship to some other note. It may seem like a small thing, but it turns out to be huge -- you have to trick your brain into forgetting about its crutches.
The whole pattern is C F Bb Eb Ab Db Gb B E A D G then back to C. The method said if you spend a week on each string, you will memorize the whole neck in a month's time. You can go back through and memorize using the sharps afterward for I guess another month of practice (but I doubt it would take that long).
It's a little boring, maybe, but I decided I'd spend the first part of every day's practice using this method for a few minutes. It doesn't take long, and it is already working. I'm just finishing my first week now and I know the E string pretty well. So I believe the method works as advertised.
NOW, in your case - you are going to have to do this in a bunch of different tunings. I don't know how many tunings are standard, but I guess it's still going to take about a month per tuning, at least at first, and then some things might get easier as you think of the whole string shifting up or down. I can't say for sure as I don't use alternate tunings.
But you can do this in such a short time at the beginning of practice, that I don't think it will take much of your attention and you'll get each tuning down to where you don't have to think about it, which is where you want to be.
From there, now you can use the chord voicing to help you figure out what riffs you want to play and be able to play them on the fly.
But if it were me, I wouldn't ever change my tuning, I'd use a 5 string.. Learn it all once.
I apologize if this isn't helpful. It looks like there are issues in metal I might not realize.