I see...
For starters, this code should help you determine how fast the mouse is moving:
backdrop on
do
mx#=mousemovex()
my#=mousemovey()
d#=abs(sqrt((mx#^2)+(my#^2)))
if d#<>0 then L#=d#
if d#>f# then f#=d#
set cursor 0,0
print "Last Move=";L#
print "Fastest Move=";f#
LOOP
Others may have completely different approaches than mine, of course.
As far as a deadzone, you can just use a percentage of your screen.
For example:
backdrop on
do
if mousex()>screen width()*.3 and mousex()<screen width()*.7 then s$="Inside" else s$="Outside"
set cursor 0,0
print s$
LOOP
(Example only covers X not Y)
