I looked at some photos on the net. The current multifuel Trangia burner is clearly a derivative of the Omnifuel. It has a cup shaped adapter to hold the burner in the proper place. I notice however that the valve adjuster at the burner has been removed. Not sure why that would be. Perhaps it didn't fit well inside the lower windscreen?

If you look at this Flickr photo stream, I think you'll see what I mean: Photos of a Trangia Multifuel Burner.

HJ