when I try to activate it it says "that omod uses a script which you have disallowed from running"

I'm not sure what would cause this... anyone?

That's odd. I've never heard of that error before. How far into the installation the did it get BTW? At least then it would be clear which part it's messing up on.

Unless, of course, it didn't get into the installation script at all. Then I don't know what to tell you except try to manually install it. I don't know if you can manually install that anymore. Been awhile since I downloaded/installed it.

Have you put a checkmark next to "Allow additional script types omod groups"?

That was it, thanks! Not sure how that got unticked.

It's not ticked by default, so you have to tick it in order to install Darn. It confused me for a time as well.