[osTirus] wrong Arp>matrix redirection?

[sfMan]

just tried recreate ostirus as stepsequencer, like in this video

I'm not very familiar with synth, but it seems to me that "Arp>matrix" mode not working properly;
I was able to modulate transpose in Matrix with Arp input as source, when Arp was in another mode than "Arp>matrix" , (f.e. "Up" mode)