This may be of some help to someone. I figured out how to get some feedback by launching the program from the command line using:
$xine --verbose
Here is the output from the point where I try to play my DVD:
gui_xine_open_and_play():
mrl: 'dvd:/',
sub 'NONE',
start_pos 0, start_time 0, av_offset 0, spu_offset 0.
xine: found input plugin : DVD Navigator
libdvdnav: Using dvdnav version 1-rc6a from
http://xine.sf.net
libdvdread: Using libdvdcss version 1.2.8 for DVD access
libdvdcss debug: opening target `/dev/dvd'
libdvdcss debug: using libc for access
libdvdcss debug: disc is scrambled
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key with player keys
libdvdcss debug: decrypted disc key is 1f:cb:69:0c:de
libdvdcss debug: using CSS key cache dir: /home/wswartz/.dvdcss//TWO_TOWERS_EXT_D1#2003090217375500/
libdvdcss error: failed opening raw device, continuing
libdvdnav: DVD Title: TWO_TOWERS_EXT_D1
libdvdnav: DVD Serial Number: 2f2304bb
libdvdnav: DVD Title (Alternative): TWO_TOWERS_EXTENDED
libdvdnav: Unable to find map file '/home/wswartz/.dvdnav/TWO_TOWERS_EXT_D1.map'
libdvdnav: DVD disk reports itself with Region mask 0x00fe0000. Regions: 1
libdvdread: Attempting to retrieve all CSS keys
libdvdread: This can take a _long_ time, please be patient
libdvdread: Get key for /VIDEO_TS/VIDEO_TS.VOB at 0x00000176
libdvdcss debug: key found in cache
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_01_0.VOB at 0x00002549
libdvdcss debug: getting title key the classic way
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: ioctl ReadTitleKey failed (region mismatch?)
libdvdcss debug: GetASF not authenticated, ASF=0
libdvdcss debug: lost ASF requesting title key
libdvdcss debug: resetting drive and cracking title key
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key with player keys
libdvdcss debug: decrypted disc key is 1f:cb:69:0c:de
libdvdcss debug: cracking title key
libdvdcss error: read error
libdvdcss debug: read error, resorting to secret arcanes to recover
libdvdcss debug: opening target `/dev/dvd'
libdvdcss debug: using libc for access
libdvdcss error: read error
libdvdcss debug: end of title reached
libdvdcss debug: 0 of 0 attempts successful, 0 of 0 blocks scrambled
libdvdcss debug: title key is 00:00:00:00:00
libdvdcss error: fatal error in vts css key
libdvdread: Error cracking CSS key for /VIDEO_TS/VTS_01_0.VOB (0x00002549)
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_01_1.VOB at 0x00061544
libdvdcss debug: getting title key the classic way
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: ioctl ReadTitleKey failed (region mismatch?)
libdvdcss debug: GetASF not authenticated, ASF=0
libdvdcss debug: lost ASF requesting title key
libdvdcss debug: resetting drive and cracking title key
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key with player keys
libdvdcss debug: decrypted disc key is 1f:cb:69:0c:de
libdvdcss debug: cracking title key
libdvdcss error: read error
libdvdcss debug: read error, resorting to secret arcanes to recover
libdvdcss debug: opening target `/dev/dvd'
libdvdcss debug: using libc for access
libdvdcss error: read error
libdvdcss debug: end of title reached
libdvdcss debug: 0 of 0 attempts successful, 0 of 0 blocks scrambled
libdvdcss debug: title key is 00:00:00:00:00
libdvdcss error: fatal error in vts css key
libdvdread: Error cracking CSS key for /VIDEO_TS/VTS_01_1.VOB (0x00061544)!!
libdvdread: Elapsed time 0
libdvdread: Get key for /VIDEO_TS/VTS_02_1.VOB at 0x00346dc4
libdvdcss debug: getting title key the classic way
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: ioctl ReadTitleKey failed (region mismatch?)
libdvdcss debug: GetASF not authenticated, ASF=0
libdvdcss debug: lost ASF requesting title key
libdvdcss debug: resetting drive and cracking title key
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key with player keys
libdvdcss debug: decrypted disc key is 1f:cb:69:0c:de
libdvdcss debug: cracking title key
libdvdcss error: read error
libdvdcss debug: read error, resorting to secret arcanes to recover
libdvdcss debug: opening target `/dev/dvd'
libdvdcss debug: using libc for access
libdvdcss error: read error
libdvdcss debug: end of title reached
libdvdcss debug: 0 of 0 attempts successful, 0 of 0 blocks scrambled
libdvdcss debug: title key is 00:00:00:00:00
libdvdcss error: fatal error in vts css key
libdvdread: Error cracking CSS key for /VIDEO_TS/VTS_02_1.VOB (0x00346dc4)!!
libdvdread: Elapsed time 0
libdvdread: Found 2 VTS's
libdvdread: Elapsed time 0
xine: found demuxer plugin: DVD/VOB demux plugin
av_offset=0 pts
spu_offset=0 pts
audio_decoder: error, unknown buffer type: 02000000
audio_decoder: error, unknown buffer type: 04000000
audio_decoder: error, unknown buffer type: 01060000
libdvdnav: ifoRead_TITLE_VOBU_ADMAP vtsi failed - CRASHING
libdvdcss debug: getting title key the classic way
libdvdcss debug: requesting AGID
audio_decoder: error, unknown buffer type: 02000000
audio_decoder: error, unknown buffer type: 04000000
audio_decoder: error, unknown buffer type: 01060000
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: ioctl ReadTitleKey failed (region mismatch?)
libdvdcss debug: GetASF not authenticated, ASF=0
libdvdcss debug: lost ASF requesting title key
libdvdcss debug: resetting drive and cracking title key
libdvdcss debug: requesting AGID
libdvdcss debug: drive authenticated, using variant 0
libdvdcss debug: authentication established
libdvdcss debug: GetASF authenticated, ASF=1
libdvdcss debug: decrypting disc key with player keys
libdvdcss debug: decrypted disc key is 1f:cb:69:0c:de
libdvdcss debug: cracking title key
libdvdcss error: read error
libdvdcss debug: read error, resorting to secret arcanes to recover
libdvdcss debug: opening target `/dev/dvd'
libdvdcss debug: using libc for access
libdvdcss error: read error
libdvdcss debug: end of title reached
libdvdcss debug: 0 of 0 attempts successful, 0 of 0 blocks scrambled
libdvdcss debug: title key is 00:00:00:00:00
libdvdcss error: fatal error in vts css key
libdvdcss error: read error
input_dvd: Error getting next block from DVD (Error reading NAV packet.)
---------------------- (ERROR) ----------------------
The source can't be read.
Maybe you don't have enough rights for this, or source doesn't contain data (e.g: not disc in drive). (Error reading NAV packet.)
------------------ (END OF ERROR) -------------------
---------------------- (ERROR) ----------------------
The source can't be read.
Maybe you don't have enough rights for this, or source doesn't contain data (e.g: not disc in drive). (Error reading NAV packet.)
------------------ (END OF ERROR) -------------------
gui_xine_open_and_play():
mrl: 'file:/usr/share/xine/skins/xine-ui_logo.mpv',
sub 'NONE',
start_pos 0, start_time 0, av_offset 0, spu_offset 0.
xine: found input plugin : file input plugin
ebml: invalid EBML ID size (0x0) at position 1
ebml: invalid master element
xine: found demuxer plugin: Elementary MPEG stream demux plugin
av_offset=0 pts
spu_offset=0 pts