You can't, right now.
the CVS code contains some additions by pooplog that allow for this, but once again, I haven't tested or really checked what he did.
Actually, If you can program the MIDI out (send some specific commands ), you could setup psycle in "synthetiser" mode, and then it can be controlled as if it were a synth.
This mode is activated when you Enable the option in the configuration, "Input/Output" tab, MIDI section ( Sequenced with Midi commands )
This mode was originally made to use a software sequencer (like cakewalk, for example), use a MIDI loopback, and then control psycle like a MIDI synth.
The information about how to use it in that mode is in the file PsycleMIDI.html, included with the distribution, in the "Docs" folder.
Just a note... There are some other limitations in this mode.
<[JAZ]> Pa pi pa pa pa pi pa.... ;ĚD