Custom NPC encounter builder
 

So I have created this custom NPC race. Seems to work good. But now I want to use it in the encounter builder but it does not show up there. I can "create new hero" and add it that way as a enemy to the party, but it doesn't show up in the encounter builder anywhere. Is there something I need to set for that to work?

Since your last question was about 5e, I'll assume that's the game system you're working on here, too. In the Help menu in Hero Lab, choose "Hero Lab Manual", and in the Gamemaster Tools section, find "Encounter Builder", and then "Adding your characters to the encounter builder".

As a note, you've posted this question and your previous question in the general information section of the forum, not in the 5e-specific section.

You need to have the creature in a portfolio, in the data folio of the game system. Put a copy in the same place as your user files, then it will be loaded into the encounter builder.