if it was my project i would add sylenth and true pianos as virtual instrument tracks and make sure the midi input is your keyboard and not midi-omni or Catanya.
 
As long as the input to these virtual istrument tracks is none or keyboard, than Catanya should not trigger them. 
 
I use virtual instrument tracks whenever possible so as to not lose track of which midi track is triggering which synth.

Ok thank you for the tip and Happy Holidays :) 

So Foster - All working for you now? Keep us updated... Cheers...

Ok will do thanks :) 

Wow!  I'm not sure if I should laugh or cry.  We first encountered the multiple MIDI sequencers bug with Catanya on 8-22-2009 and reported it then.  I'm delighted to hear it's fixed, but...
 
I would love to hear a layman's version of how the issue was ultimately resolved.  Given all the heat it generated many of us speculated that it must be so deeply integral to Sonar's code that nothing short of a complete rewrite would reach it.  Glad to hear we were wrong!

No the issues were relatively straightforward but required some time and testing to identify the issues troubleshoot and test. 
One was a MIDI routing/echo issue and the other was a multithreading issue. 

Noel Borthwick [Cakewalk]
No the issues were relatively straightforward but required some time and testing to identify the issues troubleshoot and test. 
One was a MIDI routing/echo issue and the other was a multithreading issue. 

 
Not to be petulant, but FOUR years of testing and troubleshooting?  And this fix could not have been made in X2 or X3 on initial release?  I gotta admit, this was one issue that really bugged me too.  Well, whatever is motivating you guys to get at these long term bugs and point releases is a good thing, I guess.

I'm really surprised that so many people actually know about and were affected by this issue. It really felt sometimes like it was only me and a few other people that kept complaining about it. I was certainly raked over the coals many times for bringing it up repeatedly (recent posts claiming that it is "bizarre MIDI chaining requirements" and "obscure routing" to require this functionality to work properly).
 
Well the good thing is that it has finally been fixed. I'm still trying to sort out a $99 credit I got in 2011 due to this very same issue because "the next release is still some time away". Hope there is no expiration on credits, but I can only verify the fix for myself once I get that sorted out and then upgrade to X3d.

 
This is great news.  I'm now eyeing Catanya for myself...
 
 

Well I think the important thing to realize here is that it isn't just Catanya that will now work properly, but any other plugin that works by sending MIDI events out (Out as in "back into Sonar", not out as in "out to the MIDI driver"). Basically any ARP type plugin or something like Jamstix driving a different drum plugin.