On 25 Aug 2017, at 17:34 , Hans Hagen <pragma@wxs.nl> wrote:

To: ntg-context@ntg.nl

On 8/25/2017 12:21 PM, Robert Blackstone wrote:
On 08/24/2017 10:57 AM, Robert Blackstone wrote:
[...]
%%%%%%%%%++++++MWE+++++++%%%%%%%%
\usemodule[simplefonts]
\setmainfont[Verdana]
\setupbodyfont[10pt]
does not work anymore in mkiv versions later than july 2016.

Pablo Rodriguez helped me out:

Robert,

those commands now read:

  \definefontfamily[mainface][rm][Verdana]
  \setupbodyfont[mainface, 10pt]
  \starttext
  \input zapf
  \stoptext

I hope it helps,

Pablo

It does help but for the Law of the Conservation of Trouble (or Misery)

Having properly changed my font setup ConTeXt stumbles upon things like:

“ 7~$\xrightarrow[none]$~6 progression ”

The error message is: " ! Ma error: parameter \Umathquad\textstyle is not set."

How and where can I remedy this?
This means that you haven't defined a math font so you need something:

\definefontfamily[mainface][rm][Verdana]
\definefontfamily[mainface][tt][Courier]
\definefontfamily[mainface][mm][Cambria]

or so, depending on what combination you want

Thanks for your reaction. Unfortunately it has not helped me for I have no idea how to set the parameter \Umathquad\textstyle. Just loading the fonts, as I believed you suggest in your mail, does not change anything: the compilation with a 2017 mkiv still stops at “ 7~$\xrightarrow[none]$~6 progression ”.

it compiles correctly files containing arrows ( $\xrightarrow[none]$ ) with the pre-2017 mkiv's . With my 2017 mkiv it still compiles correctly albeit not with the specified font but with latinmodern-math.otf. (Btw, I found the same behaviour for other fonts, such as: dejavu, times, palatino, bonum, lucidanova, lucida, garamond, libertine, gentium, xits, courier, and cambria.)