Hello...
I have read the entire thread but i think this may be a problem with synchronization of code and action on the pin. How about using this code snippet.
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there:
CLR pinx ;where pinx is an I/O pin with a LEd connected to it.
here: jb p3.2,here
SETB pinx
here2: jnb p3.2,hereb
sjmp there
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This small code will turn the led on if you pull the pin 3.2 to ground and will turn it off if you leave the pin floating.

The first thing i learned is that always solve little problems then look for bigger ones.

Good luck.