So I'm adding a spell to a class feature and there are 3 options for the "counts as known spell" drop down: -, yes and no. Whenever it's - and I click save and then go back in to edit it display 'no'.

Here's my use case. I was trying to make a Tiefling variant and give a different set of spells for Infernal Legacy. I'm level 3 but I don't see my replacement for Hellish Rebuke on the character sheet anywhere. So I copy the Tiefling class and see how it's all made to make sure I've got it set up right. The only thing I can see different (besides the spell selection) is that "counts as known spell" field. The copy of Tiefling has - selected but mine has 'no' selected even though I didn't select no.

To summarize, problem 1 is I cannot see my replacement spell for Hellish Rebuke anywhere on my character sheet even though I'm level 3. Problem 2, which is maybe related or causing problem 1, is that "counts as known spell" selector won't let me save with '-' selected.

Well I was able to fix problem 1 by deleting the spell addition, save the delete, then re-add the spell with the same settings. Problem 2 persists.

"Count as known spell" must have a "yes" or a "no".

It doesn't in my "COPY OF Tiefling"? (confused).

The dash ( - ) is a legacy option coming from the development environment. The dash is equivalent to a "No".