I'd say that most of your problems will go away when you start to use some decent media like TDK or Verbatim and see if the problems go away (yes i know that those brands are expensive but just give it a try to see if that helps). If you can find X-Disc dvd-r x4 than try those too (should be much cheaper than TDK but from my own experience they are very good -- i've burnt like 100 of them and even oldest one don't cause problems in both standalones and computer dvd-roms)
Did you check what firmware version your LiteOn has? Check on their webpage to see if there is newer one. Firmwares can also be downloaded from
www.cdrinfo.pl (only in Polish) or from
www.cdfreaks.com. There are also other webpages that offer firmware upgrades that are 'region free' (sometimes reffered as RPC-1).
I would also suggest looking at
www.doom9.org and especially
forum.doom9.org. You might even find someone from Croatia there
Good luck! (You'll gonna need it
)