Got that Hans. Thanks.

Now I'd like to assign a command to a(nother) new button. However, from what I understand from

\button[...,...=...,...]{...}[ref,ref,...]
http://texshow.contextgarden.net/command/detail/482

it works with a ref (*), not with a command. Following the links which lead to

\setupframed
http://texshow.contextgarden.net/cmd/setupframed

the only parameters which accept a command are top and bottom. What are these ?

Or must I proceed otherwise ?

Thanks,
Alan

(*) what's meant by ref,ref,... ? One button = one ref (or not ?)