Mine is getting quite complex, but here's an example where shift+G1 makes the mouse jump 100 counts, while simply pressing G1 makes it go 100 counts in 1 count steps:
function OnEvent(event, arg)
if (event == "G_PRESSED" and arg == 1) and GetMKeyState() == 1 then
if (IsModifierPressed("shift")) then
MoveMouseRelative(100,0)
else
for i = 0, 99 do
MoveMouseRelative(1,0)
Sleep(10)
end
end
end
end