I appreciate this is a very old thread, but in case anyone has installed Sonar X2 64 bit under W7 and is wondering whether their old Liquid Mix 32 will work, the answer is that it seems to be surprisingly straightforward to get it running.
No Jbridge needed. And no registry tweaks.
This is what worked for me:
1. Install the Firewire legacy drivers (Device Manager, IEE 1394, Update Driver Software, Browse My Computer, Let me choose, then pick the driver with Legacy in the title)
2. Install the Liquid Mix 3.01 drivers (make sure the VST installation is into a directory that Sonar reads), and plug in the Liquid Mix when instructed. Windows may not come up with any notification that it has 'found' the LM. Just keep clicking Next until the installation finishes.
3. Install the 96Khz 1.02 emulations.
4. Open Sonar. (It may hang at the scanning stage, but will either clear eventually or Scan can be stopped using Task Manager.)
5. Open Plug-In Manager. Find Liquid Mix under VST Audio Effects. Click on Plug-In Properties and tick Configure as Synth, then OK.
6. Re-scan VST plug-ins.
Liquid Mix should then be available to be inserted as a Soft Synth into the effects bin of any audio track.
There are a couple of small issues.
1. Sonar does tend to crash when exiting the project. But providing you've saved first it's not a major problem.
2. Deselecting and then reselecting the LM in Track View produces crackling. (However both Compressor and EQ can be switched in and out within the LM screen itself without a problem.)
Hope this helps anyone with an old Liquid Mix that's been gathering dust!