its possibly to do with speeds, math can be dont much quicker than positioning spites, so try positioning the sprite then adding score after its moved, something like this:
in the main loop:
IF SPRITE X(1) < 25 THEN GOSUB Score
then after the main loop in the 'Socre' routine:
Score:
position sprite 1,320,240,1
playerscore=playerscore+1
RETURN
assuming that the score for the player is 'playerscore' and that your screen resolution in the game is 640x480, that should work.
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