rbrodbec
It can but it looks like you have to change the msb/lsb calculation versus how you use it in the track inspector which is ridiculous. No .ins file makes it almost unusable for outboard midi gear at least from a workflow perspective IMHO.
If using softsynths it's not a problem.

Opinion only not fact.  I still cannot understand why you don't just set your external synths on the sounds you want to hear.  It sounds to me like the instrument definitions fan boys are just too lazy to be able to set their external synths on the sounds they want.  Or they can't.  More to the point.  Sounds like they cannot edit the patches either as well. 
 
The only thing with this is you have to be familiar with the OS for each hardware synth you have but then again you should be.  If you are not in top of how all your hardware synths work and operate then you should not be using them.  It keeps your brain active too.
 
I use 8 powerful external instruments and have no issues auditioning sounds, editing sounds and just plain leaving the sounds set after doing that. You actually don't need any program changes at all.  I find it is easier not to use them. That way they won't be switching sounds when you don't want them to.  Even if you turn everything off and come back the next day, all my synths will bring up the sound exactly as you left it too. Most hardware synths do this now. 
 
When you are ready you just print your external synths to audio.  And if you do create a patch all you need to do is save it somewhere in the synth itself.  And make a note in Studio One etc that you have used it.  You can name midi events in Studio One to anything you want.  No limit of the length of the name either.  I usually put where the sound lives in that first event name on the track. 

I get that you have chosen Cubase for its powerful midi capability. No issues there. But to choose another DAW purely based in Studio One's lack of instrument definitions is just plain dumb.  
 
I just believe the moment you have any sort of hardware synth living in your studio you really need to learn it, understand it and be able to use it to its full.  Just switching sounds remotely is not really maximising the use of that machine.  
 
I personally think its fun too getting into the OS systems of these things. They are all different.  Also I am within reach of my hardware synths too from where I am sitting making the job of setting up sounds on each one pretty easy.
 
As the late great Edgar Froese from Tangerine dream said he never uses factory presets because the guy next door has the same presets.  Once you really start either editing patches or making them from scratch then that is when the music will start to sound original.  I get that not everyone wants to do that for sure but how hard is it to simply select a patch on the from panel of the machine you are using.
 
And what about the situation when you might have thousands of patches for an instrument like the Roland JD800 that only has an internal memory of 64. Well it means you have to start loading them in, bank by bank and auditioning them.  If you only use the 64 patches for your Roland JD800 then that is really limiting the use of that machine.  You are missing out on the other thousands of patches for it.
 
Hardware synths require an approach to use them to their fullest. And it aint just leaving their patch memories where they are and using instrument definitions either.
 
Oh and what happens if you have got a synth that there are no instrument definitions for! Are you going to throw it away then.
 
Setting up multi timbral things is yes a little harder for sure but still it is no big deal. Some of my hardware makes this a snap. Others take a little longer for sure but it can be done. You can save those setups too and recall them pretty easily.  If you have multiple synths I prefer to get each one only doing one sound per midi port. They always sound better that way anyway. 
 
 

Many of my hardware instruments have editors available. That can actually run not inside Studio One but along side it.  So editing patches is actually pretty easy in this mode.  There is an amazing editor for the Kurzweil PC3K too which has a pretty nice GUI. JV2080 has a nice editor too. The editors cover every single aspect of the machine. Probably more so that what Cubase might provide. Not sure.
 
I still like editing patches on the machine itself.  Especially the JD800 which has a huge front panel and allows you to edit even while it is being sequenced. Something I find is invaluable for fine tune patches within your music.
 
Great to see you like making patches too.  Layering is also something that is very powerful.  Once you start to layer say three or 4 really nice synths with big polyphonic patches on them then you start getting into some amazing territory.  Instrument definitions won't cut a layer either.  The only way really is to make notes in your DAW about the 3 or 4 patches that are used in the layer,  where they are and how loud each one might be. 
 

djwayne
I still have the JV-1080 with expansion cards, JV-880, Emu Vintage Keys, Proteus One,and Proteus Two. I don't miss all those midi and audio cables one bit. I even eliminated a mixing board when I switched to virtual synths and sample programs. Everything is wired inside my computer. No muss, no fuss. My workflow is so much easier to deal with now. They were great back in the day, but virtual instruments and sample programs have come a long way over the years.

 
I had all those too but in the end I ended up with a JV2080 with a bunch of expansions in.  The front panel is much better and it holds 8 expansions as opposed to 4 in the JV1080. Navigating presets is a breeze too on the JV2080.
I agree with you on virtual instruments. I have probably well over 150 of them now. Most of them going into territory the hardware cannot even imagine.
 
I also use Roland JD800 and a Kawai K5000W which is also one weird sound synth. Have not quite heard anything like it actually in the virtual world either. I still have a big Emu sampler too, E5000 Ultra.  All those Proteus sound banks are available for it and they all load up and sound great. You can edit the sounds though and the effects also sound pretty nice too.
 
The editors I mentioned also allow you to send sounds and search them from your computer.  That is the way around it.  Studio One does not handle SYSEX but an editor running in tandem with it will.  Because the editor is addressing the synth directly and not through Studio One.  The editors have all the memory patches listed and will act like instrument definitions. 
 
What the hardware is great for though is creating a wall of sound over midi while your DAW does not even break a sweat. If I put all my hardware into multi timbral mode I could get something like 100 layers of music all playing at once! 
 
Studio One also has rock solid timing over external midi as well. Especially through an 8 MIDI output port device. Cubase and Logic are also excellent in this regard too.
 

So to summarize:
If you have external multitimbral midi devices and you want to layout tracks using those devices you need to per track:

Have the MSB, LSB and Program Change:
To use the patch bank # it is MSB*128 + LSB, this is entered per track along with the program change #

To switch program change using midi automation in the track you need:
100/128 * MSB for the MSB parameter
LSB Value
Program Change Value

This is not the process (that's another thread ha) but just the data you need for every bank/program change.

I believe I am correct else I just wasted a week.

rbrodbec
So to summarize:
If you have external multitimbral midi devices and you want to layout tracks using those devices you need to per track:

Have the MSB, LSB and Program Change:
To use the patch bank # it is MSB*128 + LSB, this is entered per track along with the program change #

To switch program change using midi automation in the track you need:
100/128 * MSB for the MSB parameter
LSB Value
Program Change Value

This is not the process (that's another thread ha) but just the data you need for every bank/program change.

I believe I am correct else I just wasted a week.

Depends on your device. My SQ1 doesn't use MSB/LSB. It has 2 internal banks and 2 card banks, 124-127.
In SO3 I have to check Program and set Bank to 0, Prog. to 124, and insert a controller node in the PRV to set the voice#.
 
Or I can set Bank to 0 and Prog. to the voice# and change the SQ1's bank (124-127) manually from the SQ1. Sonar can change all of these settings on it's own.

I blame Gibson, those bastards hee hee

It does not matter how good you are at what you do, the external midi device implementation of S1 is burdensome. You can spin it all you want, it's a fact. But it's workable.

Jeff's attitude towards this reminds me of a line in one of my favorite Moody Blue's song - "There is none so blind as those who will not see"