Since Sonicfire Pro is not a plug-in to Liquid Edition, you will not have direct integration. Sonicfire Pro is, however, a stand-alone application which produces WAV files that can be imported into most non-linear editing software including Pinnacle Liquid Edition.
You can import QuickTime supported video files into Sonicfire Pro. For a list of QuickTime supported formats, visit http://www.apple.com/quicktime/products/qt/specif.... We suggest that you export a "reference video" (low quality/size). Import that reference video into Sonicfire Pro using the "Choose Movie" menu item. Once your score is complete, you will export the soundtrack(s) and place the resulting WAV file into Liquid Edition.
Finishing your project with Liquid Edition will allow for some fine tuning before you render.