NeroLINUX and PIO DVR-109

I’ve installed NeroLINUX on a Slackware 10.2.
Not a supported distro but the program works great except when I burn iso images on a DVD+R.
I’ve a Pioneer DVD-109 and the problem is that Nero doesn’t finalize correctly the DVD+R that so is unreadable.
As said, the problem concerns only DVD+R.
I’ve the latest 1.58 firmware on the drive.
Anyone has the same problem?

TIA for the answer.

An update to my previous post:
the problem with DVD+R seems related to some crappy medium I’ve used and with quality media is no more reproducible.