Control layouts clashing

[Layer01]

ok i've just been mesing arround with a friends Xbox installing Roms etc.... generaly sussing it out --BINGO! Either that, or I was attempting to say "before" but it was too many letters to type-- i get my modded xbox. but i have come accross some potential problems and was wondering if anyone who has an xbox cab has found ways arround these:

i plan on using the Xarcade DIY kit (you can see how the button layout is here http://www.xgaming.com/byoarcade.shtml just open the pdf)
as far as i can see it gives each player  eight buttons layed out like this
  (W)(Y)(Wi)
  (A)(B)(Bl)
(L)(R)

with two binball buttons as (back) and a Player 1 and 2 as (start)

but when useing Xsnes9X you need to press the R-analogue button down to access the menu (in game). so is there either a way to change the button pressed in Xsnes9X or some other fix? and also i plan to wire the (back) buttons to a coin mech so to play games you'll need to insert coins but that button is the "select" in Xsnes9X and in games such a super metroid you need to hit select to change fire modes, so is there a way to map select to say the Black button (which as far as i can tell is not used in snes games) but when i tried to customise the button config i could only change the  WYAB and turbo buttons

has anyone else noticed this, i assume yes....and seeing as there are quite a few xbox cabs out there that work, what do you guys do to over come these plroblems???

[Layer01]

it just occured to me that some of these problems are only really there because i plan to make the cab a 4p one. so i could'nt have a a controller just for navigation, tucked nicely away in there as all controller ports are being used, if this added info helps....
i dont suppose anything can be done with the xbox usb ports?

[Layer01]

so NO one has come across this problem before? i am the only one to ever stumble across this??

c'mon i know i've seen requests on what to do about the analogue stick button thingy --BINGO! Either that, or I was attempting to say "before" but it was too many letters to type-- at least...