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.

Use only Liquid together with SD projects when running it with Vista as OS, I have seen some funny rendering effects with HD.

XP is a much better OS for running AL 7,2 than Vista  currently, when you want to make more advanced stuff as HD projects, buy a removable disc bay for XP and install AL 7,2 also on that bay, use the same drive letters and links,media - render files and so on that Liquid installation as in Vista  and you can open up your Vista  made projects when running XP as OS.

This workflow works well for both Vista 32 and Vista 64, 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 2009-10-14   This install workflow seems to also work well when using Windows 7 as OS, because of the lack of install compability mode for XP in W7 Home, ( regarding the install of TDK Pro )    W7 Pro or Ultimate should be used. 

Regards