IF the installation of 8.5 after X2 is already there were to cause any problems, and I do not know that it would, you could always remove X2 (search the forum for COMPLETE removal instructions), and then install it again.
 
I am not aware of any issues with installing prior versions on the same machine though.  I have several times installed prior versions and had no issues.  I had X1 and then installed 8.5 (I had removed it, then decided I wanted it back), and I did the same sort of thing with recovering X1d AFTER I had installed X2, and again did not have any issues.
 
But again, IF you did have problems, you could remove the later installation and simply install it again.
 
Bob Bone
 

You know.. maybe I'll try that Robert...
 
Thanks all for the suggestions!!
 
Stay tuned.. =)

I've transferred files back & forth with people who didn't even have cakewalk, but we always used separate wav or mp3 files/tracks. One person would make a short click track that we all used on like the 1st track. The BPM and any other notation was stored in a separate note file saved in the ftp, usually filezilla. Making sure the tracks are labeled & dated properly then sync'd with the click track. We had two mixes when it was all said and done then we could compare the different mixes to see which was the better. Hey, it worked...
 
Jay P. Lindsey
Sonar X2 + a bunch of other stuff

jayp
I've transferred files back & forth with people who didn't even have cakewalk...

Good point.  It's normal in a collaboration for the different contributors to send each other exported audio file stems rather than copies of the project.  Only one single user is responsible for managing the project.  It doesn't matter if they each use different software for recording and midi, as long they can all import and export a common audio format, e.g. WAV.

jayp
I've transferred files back & forth with people who didn't even have cakewalk...

Good point.  It's normal in a collaboration for the different contributors to send each other exported audio file stems rather than copies of the project.  Only one single user is responsible for managing the project.  It doesn't matter if they each use different software for recording and midi, as long they can all import and export a common audio format, e.g. WAV.

jayp
I've transferred files back & forth with people who didn't even have cakewalk...

Good point.  It's normal in a collaboration for the different contributors to send each other exported audio file stems rather than copies of the project.  Only one single user is responsible for managing the project.  It doesn't matter if they each use different software for recording and midi, as long they can all import and export a common audio format, e.g. WAV.