I've come across that the new math (which by the way looks really nice) requires some additional properties to be set in the font definition.

If I take the example file provided by Mikael and add the following lines

\usetypescriptfile[alegreya]
\setupbodyfont[alegreya,11pt]

It fails with the following error message:

"tex error on line 16 in file /Users/aleks/Desktop/Test Context/someformulas.tex: Math error: parameter 'limitbelowbgap' with id 36 in style 0 is not set"

Libertinus works fine by adding the following two lines

\usetypescriptfile[libertinus]
\setupbodyfont[libertinus,11pt]

Could someone enlighten me?

The font definition file is attached.

BR,

Alex