Greetings!

One can can set register levels with keys and entries
\setregisterentry[MyIndex]
    [keys:1=Sorting Key Level 1,
     entries:1=Entry Level 1,
     keys:2=Sorting Key Level 2,
     entries:2=Entry Level 2]

Rewriting the code in lua works until colon (:) is used.
\startluacode
context.setregisterentry({ "MyIndex" },
   { keys:1="C Level 1", entries:1="C Level 2"})
\stopluacode
which stops with error: <name> expected near '1'

Can the colon be escaped or underlying
   \xdef\currentregisterkeysa{\registerparameter{\c!keys:1}}%
   \xdef\currentregisterkeysb{\registerparameter{\c!keys:2}}%
   \xdef\currentregisterkeysc{\registerparameter{\c!keys:3}}%
redefined? Tried without success.

MWE (mkiv, latest beta) attached.

Thank you,
Jano