nothing in /opt on live DVD

I have downloaded, burned and run the CAELinux2007 iso image and Linux itself is running fine from the DVD, but there are no programs at all in the /opt directory (or /union/opt that it links to). So I am unable to run any of the CAE software.
What's going wrong?

I started the live CEALinux2007 DVD again and now it does see all files in /opt. At the first start of Salome it stops with an error messages but the second time it is running.
Only the network connection isn't started and cannot be started manually either (with ifup eth0).

Indeed, the DVD gave an error. I burned a new one on another brand of DVD and that one works fine.

I still can't get the network to work. The drakconnect questionnaire is the same as during startup and doesn't solve the problem, although it congratulates me at the end for being successful! Even manual configuration of the IP address doesn't help. ifconfig gives an inet6 addr. I am used to getting an inet addr. That is also what I am telling it. Strange.

I have now tried the live DVD on 4 systems. On 2 of them the network card isn't started (although it does recognize the card at startup) but everything else is working fine on these (old) systems.
On another (newer) system it does start the network but the screen is only 800x600 instead of what it should be (1280x1024).
On the last (also newish) system it isn't able to startx, it says: 'no screen found'.
It seems to me that the auto-detection of PCLinuxOS isn't working well with all systems.