http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1478734
I couldn't get it to work.
Eventually I installed Ubuntu 10.04 LTS in a VM in Virtualbox and in there it worked.
However, resolution is only 800x600. So I found this page:
http://forums.virtualbox.org/viewtopic.php?t=15679
That told me to install some stuff and then install the Guest Addition stuff. After that and a reboot HP Vroom no longer worked. But resolution was fine! Grah. Then I just used the "Live CD" of Ubuntu instead, or the normal .iso but no need to install, just boot from it.