I am not sure what video on multi output you are talking about but this link might help for multi track out for EZ drummer in Mixcraft
The video about using the parametric EQ I posted in another thread still holds true particularly the part where he shows the narrow Q boost sweep to find the boxy honky stuff. BUT note it will not alway be 800 usually depending on the particular voice or guitar the worst sounding frequency will fall somewhere in the range of 400 to 800 (again I would do less gain reduction then the 14 or so db., he was showing) but the basic theory is sound.
BUT first you should bring down the lows everything below from somewhere about 50 to 100 hz on all the tracks as a start point.
Then the other thing to think about is the technique of eq to help in making instruments more distinct by carving out (or make room) for the instruments to feature in slightly different frequency ranges from each other .
Start with cutting first often you hear an good improvement in clarity with just cutting the lows
Then :
For example lets say you find 450 hz to be very boxy on your acoustic and then hopefully it will be slightly different for the electric say 550 then you can do a fairly narrow 3 -8 db reduction centered at 450 on the acoustic and one at 550 for the electric.
If they happen to have the same boxy frequency say it seems to be the worst at 500 hz for both, you can try cutting one at 450 and one 550 with a bit wider Q or you cut both at 500
Then you can think about doing a slight 2-4 db boost with a little bit wider Q and do one centered at 300 or 400 and the other one at 500 or 600
Again all these frequency numbers are just examples of general start points and theory, ultimately it is matter of careful listening and let what you are hearing steer you towards the actual cut and boost frequency and amount choices
But when it comes to mixing multi track, the biggest mistake we all make in the beginning is thinking we have to have all the music information ( all frequencies) from all the instruments and then we often try to start EQing from there. Where what we really need to do is get rid of buildup clutter (particularly in the lows) then probably also in the mid's and then start thinking about carving out different spaces for different instruments and voice and then after all that (baking of the cake) then think about possibly boosting EQ slightly for the last bit of icing of separation.
Once you have done all and you have the rhythm section sounding good, then you can focus on the vocal, and how to mix the leads and noodling to help and not fight each other.