Found myself some 15 minutes to test the game and here's the result of the quick test.

What I changed works, but there's some glitches and oversights.

I need to change some territories in the desc_strat.txt file to have a larger population of pagans.

And I need to change the graphics back to the catholic ones (for buildings) as the orthodox ones aren't available to the Danes.

But otherwise I figured out how to change religion ...

WHEEE, my first mod ever.

Dingo