You’re right, dump the crappy media for starters. The only recommended DL media that you’ll see here on cdf is verbatim DL +R. Most folks are using MKM 001.
error 12 = “Initialization of the writing device has failed”
(we’ll need specifics from you here)
error 14 = “Media is bad”
(says it all… )
You didn’t give much detail…express version, burner, MID, burn speed, etc., etc. As platinumsword suggested, be certain you’re current, both with the app and your burner’s firmware.
For DL burns, I think you’ll be far better off with Fab’s new program…Fab 3 Beta 10 (probably last of the beta’s). There are marked improvements with the new program, especially re: DL burns. I’ve burned 25-30 DLs so far…absolutely flawless. These burns are every bit as good as what I got with dvdd (& AnyDVD) and Img. For the most part, I’ve used “clone” mode, but have had excellent results with “full disc”. Main movie continues to be excellent as well.
Fab 3 Beta 10
Hope this helps