Recording from ReaktorMidiFX Freeze
As I said earlier, MidiFX Freeze has some problems related to CC's and other non-note events, and some other issues I can't remember the details now, but basically I can't recommend it anymore. Its worth a try though, you can find it here:http://www.audiocr.com
It it works for you no problem, MidiFX free is sample accurate, meaning the events will be recorded EXACTLY where they were intended with no IAC midi jitter happening.Recording over IAC
This is the next-easiest method, which is not that easy, and as I mentioned earlier, you will lose sample accuracy as well as open up the possibility of a midi feedback loop if you're not careful (I have a Scripter work around though). Read on.
Basically you will set it up similar as the multi-instrument approach above, using the external instrument to send to IAC.
The midi feedback loop can occur if you select the track header for that Reaktor track, then midi will be routed over IAC and back into Reaktor again. Depending on what Reaktor does with that, you could get a feedback loop. So, the easiest way around that is to reassign that track to NO OUTPUT, so that basically the reaktor channel will still be there in the mixer doing its job when you hit PLAY, but there will be no track header to accidentally select.
right click on the track header to do that:
Once you do the above, then you can create a new track in LogicPro, arm it for record, and when you hit play that new midi track will be receiving the midi from the IAC port and you can record it.
As I mentioned above, this will not be sample accurate over IAC.