I spent about an hour trying to get Hexen running with all resource packs and then spent another hour attempting to fix a crash I was getting after about 15 seconds of playing It (segment violation / fault). Here's a quick guide on what I did to get things working:
Doomsday Engine Version
: Stable version 1.9.8 (build 500) (15 May 2012)
Snowberry Frontend Version
: Windows 7 Ultimate (x64)
Files To Download
(get high res texture pack)
http://cainx.free.fr/Jhexen/Xccp/deus-e ... _v1.20.rar
(hexen music pack)
(attachment below included with this thread) <--- easiest
(http://www.moddb.com/games/hexen/addons ... source-box
(http://rapidshare.com/files/31251983/jX ... x.zip.html
Archive Editor (winzip, winrar, etc)
 Download all files above.
 Run all executables from above and extract files into your "doomsday/snowberry/addons" program directory.
 Make sure all new "PK3" archives are in the "doomsday/snowberry/addons" folder.
: Open up the new "jXCCP.pk3" in an archive editor. Inside this archive, the "Defs\jHexen\Models" directory needs to be renamed to "Defs\jHexen\Auto". If you don't do this, the models will not show up. If your program won't let you rename the folder, then recreate the archive with the correct directory structure.
: this part fixed my crash issue with the resource pack from deus-ex (jXCCP.pk3). It seems that this archive is missing "rain" and "blood" DED files in the def area. These DED files can be found in the zip file provided as an attachment here or from the alternative links above.
If you use the alternative links above, look for the "FX-Rain.pk3" and "FX-Blood.pk3" files in the box resources and extract the DEF's manually and add them to the "jXCCP.pk3" archive (see below).
With the "jXCCP.pk3" archive still open in your archive editor, put the "rain" and "blood" DED files into their own DEF folder inside "jXCCP.pk3". You should have added the following files to the archive (with path):
Close the archive editor when done.
 Open up the frontend (snowberry) and add the new PK3's in the add-ons tab that we just got for Hexen.
 Give it a whirl.