Well, just my opinion as an XP user that has a pretty stable X2 with hot fix installed.
Not bitter about the situation here, I have all the PC plugs, nothing more to buy now. I don't have a touch screen nor am I planning on getting one.
Seems to me the main reason for the X2a patch is that new TS tech that is included in Win 8.
For this CW has decided to officially end support for XP.
Premature? From my viewpoint it is. This was decided before Win 8 was even launched. There really didn't seem to be much public outcry for touch screen support. I think it's a pretty big gamble to embrace this half baked idea of Microsoft and if things don't pan out the way MS has projected. They will drop support for it just like the mulitude of game controllers for PC that they discarded for Xbox. That is what I think you will see happen.
I have no immediate plans on upgrading. For the few VSTi's and a few audio tracks that my projects need, legacy support is much more valuable to me than 64 bit.
Sorry guys, it's not time to upgrade here when MS marketing dept. decides it is. I'll upgrade when I'm ready and have a need to.
With that said X2 runs as well as any other version of Sonar here, if the OP is having issues I doubt the a patch would fix it.