Update http://www.opendylan.org/building-win32-cygwin.phtml
Section 1)
current entry
  If you are going to download the Gwydion Dylan source code using CVS, you  
  will want to also install the following package:

  Devel/cvs 

change it to  
  If you are going to download the Gwydion Dylan source code using Subversion, 
  you will want to also install the following package:

   Devel/subversion