Reason MIDI Thru usb

[Pinkbox]

Hi there,

I'm having trouble syncing the arturia beatstep with the clock, and it seems to be Reason "fault"

My setup is as follow :
TR-09 is sending midi clock to my Scarlett with regular midi cable
The beatstep is plugged to reason via usb (it is the only way for the beatstep to receive a clock, the midi plug is OUT only).

All I managed to do so far is either one of these two configs :
Either Reason is master and can send a clock through USB to the beatstep, wich is synced just fine, but obviously out of sync with the TR-09
Or, Reason is a slave, receive the clock from the TR-09, but the "Send clock" button is greyed out, and the Arturia won't sync.

What I would like to have is Reason acting like a MIDI THRU, from midi (TR-09) to USB (beatstep).
And no, I don't want reason to be the master clock for all my setup, I know where it's leading to...

The main idea was to control bassimilus iteritas with the beatstep...

Any ideas would be greatly appreciated.
Thank you all.

As a gift, you can considerer listening to this great track from Clouds while you're thinking of my problem.

Cheers!