Use a "higher" version of Vista, I use ultimate, although it has been reported that even more basic versions of Vista has worked well.

Use a brand new install of Vista  with the neccessary updates done

Disable the internet connection, disable the firewall.

Go to user accounts, turn off  Control of useraccount, UAC.

Restart the machine as you are asked to, make sure you are logged in as administrator.

Do the full install of Liquid 7,2 from your hard disc, follow the pinned link in the top of the forum about license keys and so, run the update patch for liquid 6 to 7.

All the install should work well, you are asked to restart the machine, do that, do not install TDK RT.

Go to the al 7,2 install folder once again, find TDK Pro, configure the install program of tdk pro in properties/compability to "run in compability for XP" run the program, it should work now.

Start up the programs with firewall still disabled and check that all works well.

Turn on the firewall and make a windows update, the drivers for the pro bob was released on WU for V 32 in december 2006, for Vista 64, there are No drivers so the Pro Bob cannot be used.. 

Have the user account control turned off all the time when running Liquid.

XP is a  better OS for running AL 7,2 than Vista  currently, especially when it comes to burning dvd discs directly out Liquid.

If you get into trouble with that the optical drives will dissapear from the desktop, the link to the microsoft supportcenter is here.

http://support.microsoft.com/kb/929461

Edited 2008-01-15

Just rendered a 1 hour project in Vista 64 ready, have tested in both ordinary hd and uncompressed hd, project is advanced editing with mixed upscaled sd media as well as ordinary hd media, picture in picture on several timelines. Dynamic timewarp as well as linear timewarp has been used and also some Vitascene filters.  All rendered well, it is the first time with 7,2, could be the SP1 RC, thanks to Steve, in combination with the new catalyst 8,1.

Graphics card is radeon 2900 hd

Edited 2 2008-05-07

I have now been using Liquid in Vista for 5 months since the SP1 was released, all works well except for that there are no drivers for the bob in V 64, for capturing and exporting, the Canopus bob advc 300, works well. One thing noticed is that the render engine is a bit sensitive, I recommend you to have render yellow slices turned off whilst editing and avoid scrubbing the timeline when you have turned it on and wait for render to be finished.

The same goes for rendering of pink slices, just lean back and stay calm whilst the engine is running, the engine might be less sensitive when you are editing SD.