Hey... i've got a JEM 555 which originally had guage 9 strings on... and i've replaced them with guage 10, however, when i come to put the guitar into standard tuning, i get a problem... my Edge Pro II tremolo is way up in the air, as it would be if i had pushed down on the tremolo bar really hard. So for now i've got it a full tone down in D.

I'm not sure whether i need to change the tension of the tremolo's springs, or whether i need to change the neck tension, or whatever... so any help would be greatly appreciated.

throw a couple springs in the back (take off the back plate, you'll see what i mean) and then have it re-settup for those strings...

my guitarist has a JEM and i'll be damned if those edge trems arent the biggest PITA's ive ever come across
"insert witty somewhat racial, innapropriate, degrading comment here"
Follow these simple steps

Tuning Floyd Rose:
1) Loosen the locking nut
2) Set your fine tuners to middle position
3) Tune up your guitar to standard or whichever tunings u wish
4) If the floating bridge comes out, loosen the tunings and then tighten the springs in the tremolo cavity at the back, if the bridge sinks, then vice-versa, until the bridge is parallel to the body.
5) If you're happy with your tunings and your bridge is well centered, lock in the nut
6) Tune again using the fine tuners

More info on tuning floyd roses - http://www.floydrose.com/originaltremolo.html
Info on changing strings - http://www.ultimate-guitar.com/columns/features/steal_this_video_re-stringing_guitar.html
Picture guide on how to perform the #4 step mentioned above - http://www.fretnotguitarrepair.com/floydrosetremolo.htm
"Play with your ears" - Yngwie Malmsteen, Paul Gilbert
Thats what she said...
yeah.....but the tension on the trem is too much. at tune its pulling the actual trem block up off the body
"insert witty somewhat racial, innapropriate, degrading comment here"