After configuring Stutter Edit (SE) as a "synth" I closed Sonar and ran the registry editor by typing regedit into the search programs and files box at the bottom left of the desktop. Once in the registry navigate to HKey_Current_User. Expand that then on to Software to Cakewalk Music Software to Sonar Producer to Cakewalk VST64 to Inventory and finally all the way down the (in my case) very lengthy list to c:program files (x86)/cakewalk/vstplugins/Izotope Stutter Edit.dll (or where ever you stored the .dll to) and highlight this.
To the right of that you'll see all the dll instructions and parameters. If you don't know how to deal with these...PLEASE BACK UP YOUR REGISTRY FIRST!!!
While there are many parameters to choose from the three you'll be looking for are:
Full Path
IsSynth
IsX64
The full path probably says c:\programfiles (x86)\cakewalk\vstplugins\izotope stutter edit.dll (or where ever you stored the .dll file)
This should be changed to c:\programfiles\cakewalk\vstplugins\izotope stutter edit.dll (or where ever you 64bit vst folder is)
IsSynth and IsX64 will probably have an ending value of (0) in the Data list
This should be changed to (1)
You make changes to these three lines by right clicking the labels (i.e. Full Path, IsSynth, Isx64) and selecting "modify".
The path can just be edited or retyped and the the other two will just be changed from 0 to 1.
Again YOU WILL BE MAKING CHANGES TO THE REGISTRY HERE...BE CAREFUL .
If you've done it right Stutter Edit should now show up in your Soft Synths menu and be able to be selected and inserted in the FX bin of a track. But remember also you'll need to create a midi track whose output is Stutter Edit to control it.
HTH.