Product review (5 stars): New design for drainage - works great!
Did the trick!

The only suggestion that I have for installation is to realize that you may not be draining because of ice backed-up in above the duckbill.  This is a change in design and moves the trap to the U-bend.

So, if you're installing take a small screw driver poke it up to see if there's ice where the duckbill was.  If there is ice, you may need to melt it to get the drain working properly.  Otherwise, you're still going to get ice on the bottom of your freezer.  (Like happened to me.  I had to take it all apart again!)