Again, I don't have CW, so I can't tell you specifically for that s/w but for Sound Forge, you open the file, convert it to mono using the Channel Converter plug, choosing only 100% of say the right channel, save that to a new mono file.
Re-open the stereo file (or undo the last changes) and use the same plug, this time using 100% of the left channel and save that to a new mono file.
The import those new files into CW as individual mono tracks.