This, provided I've done everything according to instructions, does not seem to do anything to change the situation, I'm still only hearing the internal soundfont sound. But there are also steps you mention that I still do not grasp how to do if they are even possible to do as described.
For one thing, the program itself has no specific "sample rate settings" that I can find, let alone adjust (screenshots with to go with your instructions would've been of tremendous value). I can set the its audio preferences to "same as system", which should suffice for that purpose, but that still leaves the question of how to specifically set it to "monitoring" a-la any half decent DAW. This is something I'm starting to think simply does not exist in BBox yet, at least not on my platform.

So, I'm thankful for your effort and attention (I don't see anyone from PG offering so much as a word yet), but I'll need far more details, preferably visual ones as well, in order to get to the bottom of this.

There's only one thing to do in crisis like this - Sleep on it!
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BBox 2022 Audiophile, Mac Pro Intel, OSX 10.6.8, 800x600 (TV VGA)