On page 100 of the manual it shows listing the config fuses in a different format than you've been using. Could be worth trying.

In the above you've got #define OSC 20 and you need to get rid of the pound sign. I'm assuming that would be the same for the code-size statement also.

You could also do most of the above with the CONFIG1=xxxxxxxx and CONFIG2=xxxxxxxx. Something else to try maybe.

Just a few thoughts that may be horribly bad.