On the [Miracle Piano Teaching System - R.I.P. 8/2021 ,] Roland HP 137R, Casiotone CT-460, and Casio CSM-10P, no GM support. (I have even made a MIDI-OX Data/Patch Map that maps the GM MIDI events to the Miracle MIDI events.)]
On the Yamaha DD-14, partial nor no GM support (only some of the drum note numbers match its GM mapping, thus is more intended for drum MIDIs).
On the Casio LK-100 and CTK-491, partial GM support (e.g. GM mapping can be enabled) and only 5 (1-4, 10) MIDI channels supported (but synth can be doubled via multitrack recording).
On the Casiotone CT-460, only 4 MIDI channels supported.
On the Yamaha PSR-170 (NEW!), partial GM support (without pitchbend, modulation, and RPN support. However using Portamento Control, it makes it possible to bend a note only by semitones. Only reset is GM ON SysEx) and only 8 (1-7, 10) MIDI channels supported.
On the Yamaha SHS-300 (NEW!), partial GM support (with only 12 possible voices, which are 11 melodic and only 1 drum kit in which that is the Dance Kit and there is no such Standard Kit, voices numbers that are not listed will not play).
On the Yamaha DD-50 (NEW!), partial, but not even full GM support (no SysEx!). Yamaha has not listed the GM-mapped backing voices, but I did list them properly myself, detailed in my post here:
http://vogons.org/viewtopic.php?f=62&t=73581On the Miracle Piano Teaching System, only 8 MIDI channels supported.
On the Roland HP 137R and CSM-10P, either only 1 MIDI channel supported or all MIDI channels share the same single MIDI part (a.k.a. Omni).
For Edirol (Roland) SD-90 in GM2 mode, there are 4 sets: Classical, Contemporary (default on GM2 reset), Solo (known to the infamous Romantic TP instrument used in ZUN's Touhou music), and Enhanced. Enhanced set however is limited only to 3 parts at a time in GM2 mode so it was not on the list to avoid myself doing the advanced setup in Native mode for the set.
On Mary's Yamaha Clavinova CLP-535 (may be temporarily unavailable), partially supported GM/XG support, but only preset voices and 3 additional drum kits (a.k.a. 2 drum kits + pop latin kit). If I want to convert MIDIs to audio from her piano, I have to email Mary with the attachment containing the MIDI files. Her email is dmwieserATcenturytelDOTnet
Also, check inside the MIDI files as well to see if it is a GM, GS, or XG compatible. For example the selected MIDI files contains a GS Reset SysEx and you were meant to select SD-90 GS Mode but select SD-90 GM2 Set instead, the MIDI file will just direct the SD-90 into the GS mode and not use the GM2/XGlite sound bank.