My first attempt wasn't very successful.
I can get to the first screen. I can define a new guest machine. However, when I try to start that machine (new VDI, and pointing to the real DVD drive, with a WinXP PRO CD) It complains, immediately, and says to check the log. Okay, the log says it failed to find some files, in my old VirtualBox directory (which is just left over from before, the old VBOX was not installed). I have no idea where it is getting that stuff from. I don't think it even gets far enough to think about using the DVD drive.
It also appears that the VBOX_USER_HOME environment variable is used in some places, but ignored in others (I HATE using that %HOME% directory). However, that isn't what is causing the problem. I deleted the whole directory from the old VBOX setup, and it still wants to use it. More work to be done there.
2Andi B.: Network is just the same as it was in older version. NAT just works, as previously. But TAPOS2 is broken -- needs to be repaired. Ping/tracerte not working -- yes.
TAP has been badly broken, forever. It worked, with the old VBox but killed machine (host and guest) network performance. NAT worked fine.
But I suspect it is the same as on Windows an Linux hosts.
I don't understand what you mean by this. TAP is not used with windows, or Linux (AFAIK). There is Bridged network support, which works fine (in windows host, at least).