Can't get lookahead CALT to work

I’ve done lots of backtrack CALT’s successfully, but I’m trying a lookahead. However, I can’t get it to work.

I press the “n” which gives me a natural sign. When I then type a numeral, it should make the natural superscript, but it does not.

What am I missing? Maybe I’m not understanding “lookahead” correctly. I don’t want anything for the backtrack because I want this to work no matter what comes before the “n.” Thanks!

By the way, I thought you might like to see some samples of what I’m using this new font for. Except for the notes on the staff, everything else was typed in using simple, intuitive key combinations.

The lookup is not attached to a feature yet, hence " <-not used ".

Got it, thanks! I just needed to drag the CALT into the ltn script.

So it seems that CALT lookups are not features until they’re applied to one of the scripts? Am I saying that correctly?

Also, it seems that Single Substitutions are grouped as lookups, but I don’t see them in the dflt or ltn scripts.

OpenType features in a font will be applied if the shaping engine decides to process one or more features. Then all lookups within those features are applied, in general in the order of the lookups, as shown in the Lookups tree, from top to bottom.