[magick-users] no decode delegate

[omicronpersei8 at imagemagick.org]

> > As root, 'convert B1.tif B1.ps' works as expected and produces B1.ps.

Most likely a permissions problem.  Try

  ls -l /usr/local/lib/ImageMagick-6.?.?

and most likely the folders in that path cannot be read by anyone other
than root.