using a pot to control a time range

[peterdeco1]

Try this. I've used something similar to it on a 12F675 and had no problems. You should be able to turn on the LED for up to 255 seconds (the maximum byte value).

CMCON = 7 'comparators off
trisio = %11111111 'ALL INPUTS - HIGH & LOW COMMANDS CONVERT TO OUTPUTS
DEFINE OSCCAL_1K 1 'Set OSCCAL for 1K device
POTVALUE VAR BYTE 'POTENTIOMETER VALUE VARIABLE
LEDTIMER VAR BYTE 'LED TIMER VARIABLE

START:
LET LEDTIMER = 0 'RESET TIMER TO 0
Low GPIO.4 'TURN OFF LED ON GPIO.4
PAUSE 5000 'STAY OFF FOR AT LEAST 5 SECONDS
ADCIN 1,POTVALUE 'READ VALUE OF POT
IF POTVALUE = 0 THEN START 'STAY HERE OFF UNTIL POT IS TURNED

LEDON:
High GPIO.4 'TURN ON LED FOR 1 SECOND INCREMENTS
PAUSE 1000
LET LEDTIMER = (LEDTIMER + 1) 'COUNT SECONDS
ADCIN POTVALUE 'READ POT VALUE
IF POTVALUE > LEDTIMER THEN LEDON 'STAY HERE ON UNTIL LEDTIMER = POTVALUE
GOTO START 'LEDTIMER = POTVALUE GOTO START & RESET