Following up on my own note, I see that this fails under LMTX if 
compiled in a clean directory, but succeeds if first compiled with the 
troublesome line removed, and then, restoring the line, compiled a 
second time. It also works by placing a .tuc file from an older version 
of the document into the directory before compiling. Very strange 
indeed. The expected output, from one of those successful compilations:

So. I am clearly doing something wrong, but sometimes LMTX is letting me 
get away with it.

-- 
Rik

On 10/27/2021 21:47, Rik Kabel via ntg-context wrote:
>
> Hello list,
>
> The following fails with ConTeXt  ver: 2021.10.24 21:45 MKIV but works 
> with the companion LMTX. The error message is:tex error       > tex 
> error on line 6 in file G:/TestConTeXt/convert.tex: ! Incompatible 
> glue units , pointing to the second \convertnumber line.
>
>     \definelabel[XX]%[text=,before=,after=,alternative=inright]
>     \startTEXpage[offset=2em]
>      abc\XX[xx]\par
>      \ref[number][xx] ·
>      \convertnumber{r}{1} ·
>      \convertnumber{R}{\ref[number][xx]}
>     \stopTEXpage
>
> In this case I am trying to display with roman numerals the number 
> generated in the label created through \definelabel.
>
> Suggestions welcomed.
>
> -- 
> Rik
>
>
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