how to use designsize

["Wolfgang Werners-Lucchini" <wwl@musensturm.de>]

Hallo!

After asking some questions about installing metafont's, I have not made
any progress.

I would like to show the problem with J. Knappen's EC-fonts.

To access this fonts I adapted my little typescript:

-----------------type-kna.tex--------------------------
\starttypescript [serif] [knappen] [name]
  \definefontsynonym [serif] [ecrm1000]
\stoptypescript

\starttypescript [serif] [knappen] [size]
  \definebodyfont [5pt,6pt,7pt,8pt] [rm]
    [tf=ecrm0900 sa 1]
  \definebodyfont [9pt] [rm]
    [tf=ecrm0900]
  \definebodyfont [10pt] [rm]
    [tf=ecrm1000]
  \definebodyfont [10.95pt] [rm]
    [tf=ecrm1095]
  \definebodyfont [12pt] [rm]
    [tf=ecrm1200]
  \definebodyfont [14.4pt] [rm]
    [tf=ecrm1440]
  \definebodyfont [17.28pt] [rm]
    [tf=ecrm1728]
  \definebodyfont [20.74pt] [rm]
    [tf=ecrm2074]
  \definebodyfont [24.88pt] [rm]
    [tf=ecrm2488]
\stoptypescript

\starttypescript [Knappen]
  \definetypeface [Knappen] [rm] [serif] [knappen] [knappen] [encoding=ec]
\stoptypescript
---------------------------------------------------------------

and used the following testfile:

--------------------tst.tex---------------------------------
\usetypescriptfile [type-kna]
\usetypescript [Knappen]
\setupbodyfont [Knappen]
\starttext
\chapter{Fest}
Gottes.
\stoptext
-----------------------------------------------------------------

Problem: 'ecrm2074 at 600', which exists, should be used!
              'ecrm1200 at1036.8' is used  instead!

How can this be corrected?

Thank you for your help!

Wolfgang