What I suggest is that you have one of the 3 latest builds, the Launcher (version 3.1 will do nicely), and the 3.5.6b mediaVP file. You shouldn't need to extract any of the files from the VP, but just have it in the root Freespace2 directory. Once the launcher is in place and you've made your various selections, be sure to add the command line tag "-t32" in addition to your -htl tag. If you plan on running FS2_Open from a shortcut rather than through the launcher each time, then either copy these tags into the shortcut parameters, or select the feature that will apply the tags whenever FS2_Open is launched, though it may have some problems with FRED. That should do it. While you're getting the 3.5.6b media VP, you might want to complete your Lightspeed FS2 Shinemaps and grab the zip in Lightspeed's stickied thread. You may also choose to get his WIP 32-bit tga planets, located in another thread further down.
Later!