For those that care, MIDI Yoke NT's setup installation will be able to install a virtual driver that will work for 32-bit applications running under x64. It's a much better solution to LoopBe1 (despite being native 64-bit) for all purposes intended, unless you're willing to pay for the much better payware version.
The downside is, you cannot adjust the number of virtual ports with MIDI Yoke, since the control panel applet wasn't designed to work properly under 64-bit. Otherwise the vsti chaining method is fine.
I will provide a link, until advised to take it down:
http://djtbmx.stdrand.com/junkpile/yamahaxgvsts.rar (includes MidRadio Player 7's S-YXG2006LE, you can figure out the rest)
The problem with LoopBe1 is that it's been designed strictly to MIDI specs, so excessive MIDI data bandwidth (in this case a WALL OF PITCH BENDS) would trip the loopback warning, and cut off transmission, which is kind of silly since you're not generally dealing with MIDI-standard hardware limitations.
PS: I would personally use VSTHost instead of SAVIHost to get around polyphony limitations, and the possibility of omitted System Exclusive messages, in addition to being able to place a limiter at the end of the signal path.