CD Burning Errors

System = Celeron 766, 128Mb Ram, Panasonic CW-7502, Advansys SCSI controller.
OS = Win2k.

Problem = CDRWin V4.0 reads PSX game cd but errors on writing. Backs up ISO image of data files ok but not a backup image of game file. Changed softwareto Nero V5.5 which reads & writes without question but the written CD is unreadable.

Any clues?