Yamaha DTXpress/DTXplorer/DTXtreme

I KNOW I have been told about rejection...I am having a time with my 
snare-HH-and bass drum.  I can't seem to pin point WHERE this static 
sound is coming from(snare/HH/BD).  It seems to happen if and when 
all three are triggered at the same time...so how do I set 
rejections on all three, and what input rejects what?  It sounds 
confusing.  
Tonite I wrote down ALL my custom kit settings on that trigger map 
sheet, and I was reminded about how LITTLE I know about this kit.  I 
wanna hook up my MidiKITI, and plug in the extra cymbals and pads, 
but I feel like I will be opening up a Pandora's box, as I still 
have a TON of learnin' to do on the DTX!!  Well...ok...that's how I 
mastered my computer...dealing with problems! I'll get the hang of 
this but it just don't seem to come fast enough!
  It's having a bunch of great guys in this forum 
that help thick skulled folks like me finally learn what the DTX is 
all about. Many thanks for your guidance and patience.  That being 
said...here goes...
Some of the note numbers are all used up, specifically my HH. In V=1 
my note is 52, but for V=2 it says "all notes taken"...HOW can I 
reverse that, or delete it from memory and start over?
What is AltG for and what does it DO?  I have most of my pads set 
on  SEMI, except for snare/crash...that is on POLY, what does this 
mean or do?
HOLD is set to OFF on all pads...what would happen if I turned it on?
KEY OFF is set to DISABLE...what would happen if it is enabled?
FUNCTION on all pads is set to NORMAL-what's this do?
This PAD SONG thing-does that mean if I hit a certain pad, that one 
of the preset songs in the DTX will start/stop?
AND HERE'S A REAL GOOD ONE....I have "tom1" only programmed for 2 
voices, when I got into mapping these settings, I saw that there was 
a setting for "tom1R" and "tom2R" as well as settings 
for "open", "openR", "close/closeR".  Does this mean I have to have 
settings (voices) assigned to these, or are they for dual or triple 
zone pads like the TP80S?
Also what does "COPY TO INPUT" mean?  If I copy the saved settings 
for say HH which is physically in input 8, and saved them to INPUT 8 
does that mean input 8 has just my saved HH settings or does it have 
the HH settings PLUS my saved user kit?  AND WHERE is input 8?  How 
do I acess that input?  Am I making this too complicated?
Iknow...I know...read the manuel!  I have, but under some of the 
explanations for some of these things asked,there is only given 
vague 
information.  I really don't wanna mess up my custom kit by 
experimenting. I am having enough trouble with rejection, gain and 
all.

Also..one more time on the HH...should GAIN be set high or low, I 
have mine set at 20...could this be why I am getting cross talk?
Appreciate all your help and suggestions, and patience with me!!!
Jade:)