Thanks for that, Telecharge.
 
That certainly would speed up the process, but if those are the default instruments that are used when playing back a MIDI file in say, Windows Media Player, they aren't really of sufficient quality or realism. I see references to Roland and Yamaha in there, and those are known to be decent MIDI sound modules. I wonder if those wavetables can reproduce those modules? Guess I would have to explore it. I've been avoiding anything built into Windows because in my experience the instruments have been pretty basic and cheesy-sounding. Just enough to check a MIDI file to see if it's working before getting on with using with a sound module.
 
I had high hopes for the Rapture instruments, but as I mentioned, as soon as I ran into a wall with getting that running I had to give up. I wonder if my laptop just doesn't have enough resources to make it work, or if the problem is "between the headphones", as they say.

In order to use the instruments in the Instrument list, you have to have one of those instruments connected. Selecting, for instance, "Roland GS" as an output will produce no sound unless you have a Roland keyboard or sound module which uses those sounds connected.
I've always thought a MIDI Master would be useful, until I realized I already have one; the volume knob on my MIDI keyboard.

In order to use the instruments in the Instrument list, you have to have one of those instruments connected. 

 
That makes sense. I wouldn't think a PC would be shipping with anything other than the simple synth sounds of Windows.
 

I've always thought a MIDI Master would be useful, until I realized I already have one; the volume knob on my MIDI keyboard.

 
But I'd like something that doesn't require human intervention, i.e., that is stored in the project. The audio track master in SONAR works great for this, but there doesn't appear to be a MIDI equivalent. This seems like a easy thing to implement, since the individual faders for MIDI tracks work fine. Why can't those all be routed to a master bus?
 
If there's nothing in Home Studio to allow this, maybe the answer IS to route the audio out of the MIDI module back into SONAR. I sense possible latency issues arising with that setup though.
 
Getting the RAPTURE library to work sounds time-consuming but I may go that way eventually.

You can Group all your MIDI tracks so that 1 volume slider will control all the volumes. That would be kinda like a Master volume.
But you wouldn't be able to control the individual tracks's volumes without removing them from the Group.

Well that made me look into "groups", and I discovered the concept of "quick groups", a temporary grouping by holding down the control key while adjusting one track's fader. That way they're only grouped momentarily.
 
This is probably good enough for now. Thanks!

You should use the TTS-1 or GM,, it was made just for this purpose, it plays all GM files the way they should sound.,, never use MS wavetable that's like 100 years ago. 
If you un tick all the midi out boxes in preferences   Midi files will automatically open in TTS-1. 
Always OPEN midi files

There's no TTS-1 in Home Studio AFAIK.

There is in mine? 

Cactus Music
There is in mine? 

Then the Cakewalk compare versions page must be incorrect.
 
https://www.cakewalk.com/Products/SONAR/Versions

After reading this exchange and not having the product, I emailed presales support about the discrepancies between the documentation and the product web page. There are errors on both pages. They have sent notices to the appropriate groups to correct them. Nine minute turnaround for the support ticket on a Saturday, not bad. For the record, SHS contains:
TTS-1
SI Suite
Rapture Session