Answer from Christian Töpp:
Make sure that /usr/X11/lib/X11/fonts/Type1 or similar exist.
If it exists, but xset -q doesn't list the path to the Type1 directory add this path to the XF86Config
Make sure that XF86Config contains in the Section Modules an entry Load Type1
Restart X.
Verify with xset -q that the Type1 path is recognized by X.
If this is all true, but Scribus won't start, do the following:
1) Create a textfile containing your Fontpaths.
e.g:
/usr/share/fonts/Type1,
/usr/X11/lib/X11/fonts/Type1
2) Save this file as .scribusfont.rc in your home directory.