Tracktion (Waveform) and ReWire: Possible to record midi input + use as a slave

[SteffHell]

Hello,
I stumbled across this video that talks about combining Reaper with Tracktion via ReWire:


I wanted to try that myself, in both ways.

With scenario 1 (Waveform to Reaper) it was all working, as expected. I could...
* create a midi track in waveform
* add a "ReWire Device" to that track
* choose Reaper as a device and route the Waveform track to a Reaper midi bus
* In Reaper I could use that ReWire bus as input
=> As a result I could play AND record that Waveform track in Reaper

Scenario 2 (Reaper to Waveform) was working only partly.
* In Reaper I routed to a rewire bus as "Midi Hardware Output"
* In waveform I, again, added a "ReWire Device" to that track plus a synth
=> As a result I could play the Reaper BUT NOT record it in Waveform

Questions:
1) Should recording a ReWire track in Tracktion also be possible?
2) If so, is something wrong with my setup (see screenshot)?



Intuitively I wanted to change the track input (red circle) but could not find anything better?
3) Or, is recording ReWire input generally not possible?
4) If not, does that have to do with the concept of master and slaves and does Tracktion only work as one of them?
(I read a very old post somewhere that said that Tracktion could only be used as a Master, not sure if that still is true or ever was, but hoping someone can put these bits of information together for me.)

[chico.co.uk]

Route the audio output of track 1 (with the reaper plugin on it) to track 2, as an audio input, arm that, and record to track 2.

Tracktion/Waveform can be a Rewire master, but not a slave.

[chico.co.uk]

Actually, you don't need to route the audio output of track 1 anywhere, just add a second track, and make the input an"Audio Track", and choose your track 1. Arm it, and record.