Followed Cakewalk's instructions here

http://www.cakewalk.com/Support/kb/reader.aspx/2007013099

Sound Forge shows up on the drop down and can be opened but the selected clip does not open in Sound Forge.......kind of defeating the whole purpose of registry editing. 

I know Sonar has some audio editing capabilities but Sound Forge IS and audio editor and does it very well. 
Been using it for years inside Cakewalk products, Has anyone figured out the next step after opening Sound Forge in dropdown......getting the clip loaded up for editing? 

IIRC I had to use the term "wave editor" not "generic" to make the wave appear. Have not done this yet on my new machine so we'll see!

I had it set up in X1 with 3 different wave editors Sound Forge, Audition 3, and iZotope's RX2 Adv and it carried over perfectly to X2.
I can select a clip or any part thereof in the time line and it opens perfectly in my chosen editor.
 
Save the following as a .txt file (windows notepad will do). Once that's done change the file extension to .reg
 
[HKEY_LOCAL_MACHINE\SOFTWARE\Cakewalk Music Software\Tools Menu\Sound Forge 10]
"exePath"="C:\\Program Files (x86)\\Sony\\Sound Forge Pro 10.0\\forge100.exe"
"MenuText"="&Sound Forge 10"
"StatusBarText"="Run Sound Forge 10"
"Type"="WaveEditor"
"HelpFilePath"="C:\\Program Files (x86)\\Sony\\Shared Plug-Ins\\Help Files\\forge100.chm"
 
Double click the file and your registry will automatically be updated.
 
do the same with the following:
 
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Cakewalk Music Software\Tools Menu\Sound Forge Pro]
"ExePath"="C:\\Program Files (x86)\\Sony\\Sound Forge Pro 10.0\\Forge100.exe"
"HelpFilePath"="C:\\Program Files (x86)\\Sony\\Shared Plug-Ins\\Help Files\\forge100.chm"
"MenuText"="Sound Forge Pro"
"Type"="WaveEditor"
"StatusBarText"="Edit the selected audio event using Sound Forge Pro"
 
 
Replace the relevent paths for your program like Sound Forge.