I've had a problem with R-snapshot since getting rid of systemd on my Jessie install.
The squashfs is made but then it ends with no dvd image made in the target dir.
In the error file there is this line:
/usr/bin/refractasnapshot: line 599: xorriso: command not found
(which I don't think is the cause)
I ran with the 9.1.6 from testing archive, though I had this problem with an earlier version too - it was definitely after my fight with systemd...
any pointers as to what I need to find is installed or not? thanks