Well I had the same problem with graveman and xroast.
As for xroast I emerged (I'm using gentoo) both cdrtools and prodvd but it didn't change a thing.
Then I unmerged cdrtools and emerged (uninstalled and installed) dvdrtools and dvd+rw-tools.
That didn't work either, but then I just did the folowing. (still with dvdrtools and dvd+rw-tools installed)
Lunch graveman
Goto menu file->preferences and "External programs" tab and click "scan again for external programs.
flac got a red ligh and mkisofs got a orange ligh, the rest got a green light.
Before that most of them were red.
After dooing this it worked perfectly. I now detects the correct media and I just recorded a DVD-R. It's simple and does the jobs.
Since it doesnt apears to have a data check I do: (to check if the data was recorded ok)
do to the dir in the hard drive where I got the files from and do a "md5sum * > ~/hd.md5"
Mount the dvd, change to it's dir and do "md5sum * > ~/dvd.md5"
then change to my home and do a diff between the files "diff hd.md5 dvd.md5". No output sould exist.
If the files were created ok it at least was able to read the contents of the dvd, so there should be no errors.
The md5 check is just to make sure the files have exactly the same content.
When the dvd has error md5sum reports them to stderr.
Hope this helps
