I don't think this is a dirt. Clone 1 errors usually indicate a confused bitrate controller - meaning all of a sudden CloneDVD detects the transcoded movie will not fit on the disc!
(gor & armin correct me, if I am wrong)
Please send a report to email@example.com, including:
1.) CloneDVD Version
2.) What DVD caused this (Title, EAN code, etc.)
3.) All .IFO files of this DVD zipped together with your mail.