I took a look at your HEX file, and it looks like the function for initializing the ADC was placed at address 0x1C, which is in the area reserved for the P-Star's bootloader (0 to 0x1FFF). When your code tries to call that function, it will end up starting the bootloader instead.
Instead of just putting "org 0x2000" on your
main function, you will need to find a way to move all functions, data, and entry vectors be at 0x2000 or above.
I recommend checking the documentation of mikroC PRO for PIC, and in particular the linker, to see if it has some kind of option to specify what range of flash memory to use. Please let us know what you find out.