I have this subroutine:
.BUTTONPRESS
Lbl BTN
For(I,1,{R})
I-1*5+1üJ
Text(88,56,{R+J+4}åDec)
If (({R+J+2}=1) and ({R+J}-S+1÷X) and ({R+J}+5ùX) and ({R+J+1}+3=Y)) or (({R+J+2}=4) and ({R+J}-S+1÷X) and ({R+J}+5ùX) and ({R+J+1}-S=Y)) and {R+J+4}
0ü{R+J+4}
{R+J+3}üF
1üG
Pt-Chan{R+J},{R+J+1},{R+J+2}-1*16+Pic4)
Pt-On({R+J},{R+J+1},{R+J+2}-1*2+1*8+Pic4)
End
End
Return
but 0 doesn't get stored into {R+J+4} for some reason. 'elp?