Rob,

Yes you're not testing the correct bit for the actual output of the Comparator..

Look at my post again where I listed the things you need to correct. Look at item 2.
I point you to where you can find the answer of which bit in which register to test.
I also point you to where you can determine what the output of the comparator will be for different configurations and physical connections.

Have a read of this info again, I'm sure you'll get it.

Regards