Do you know the basic principles to operate TM FX ?

1. HW inputs are always passed through to the application.
2. Mute on inputs is only relevant for a submix, the application still gets the signal from HW input.
3. In submix mode click to an HW output (which is the submix) and set the faders of
- HW inputs (whats connected to your device) and
- SW playback (signals that come from your applications)

Now one basic example how routing works:

All you need to do is to connect
- outputs of your outboard device to i.e. Analog 3+4 IN
- inputs of your outboard device to Analog 3+4 OUT

Now the routing part, assuming your DAW sends something out to Analog 1+2

1. click to HW Output "Analog 3+4" and raise the faders of SW Playback "Analog 1+2" up to 0db
Temember, everything which comes from application/DAW you see on the SW output channels.

Now you should see:
- on your outboard device a signal coming in (assuming it has such controls)
- as the outputs of your outboard device are connected to Analog 3+4 IN, you should see also here a signal coming in.
As you know, TM FX passes all signals of HW inputs to the application/DAW:
- so you should also see an input signal in your DAW at Analog 3+4

This routing you can store to a snapshot (right side of TM FX).

And the whole setup you can store two ways
a) by storing snapshot and workspace to disk (TM FX: File-> Save Snapshot as, File -> Save Workspace as)
b) by storing snapshot and workspace to one of the 30 Workspace Quick Select Slots (TM FX: Workspace Quick Select)

I personally do it both ways:
to a) it's easier in handling, you can save and restore both
to b) you save the snapshot and workspace to a folder in your home directory which you (should) backup.
Then you can restore snapshot and workspace easier after new installation or on other PCs.

Here a TM FX primer that I wrote, which contains the overview below to make routing more clear:
https://www.tonstudio-forum.de/blog/ind … rnal-equi/

Also watch the RME video tutorials and read the handbook where TM FX is also explained:
https://www.tonstudio-forum.de/blog/ind … al-Videos/