Choraz - Sorry, the answer I was giving you was for general editing using Wavelab. Now that I've had a chance to try it, I see what you mean. However, it is appears to be specific to the mono-to-stereo conversion you are trying to do.
If, for example, you process the clip in another way - say normalizing or pitch correction - Wavelab will apply the change to the open file. Then when you save it and go back to Sonar you will get the "file changed" message.
However, as you said, when processing the wave from mono to stereo, Wavelab actually creates a second file. Since the original file has not been modified, you don't get the "changed file" notice when you return Sonar.
Can't help you out, except to confirm that mine is working exactly like yours is. However, it seems to be just for that particular process. Other edits in Wavelab behave as you would expect them to.
A suggested workaround would be to save the "second file" (stereo) and then import it into Sonar using the File -> Import Audio command. It's an extra step - plus you have to line it up - but it should work.
Teacher - Wavelab can serve as a wave editor in addition to being a great Mastering program. It has some features and functions you can not find in Sonar (such as a drawing tool which allows you to edit the actual waveform to remove a glitch for example). You would in this case use it to edit a clip within a Sonar track, and then return to Sonar to finish mixing. They work well together, and Wavelab actually appears on the Tool menu of Sonar. You just highlight the clip, and use the menu to launch Wavelab with the clip already loaded.
Once you have finished mixing your project and export a final stereo wave file, you can use Wavelab to master it. Here, of course, you would not want to return the file to Sonar.
PS I don't work for Wavelab (or Steinberg); however, any renumeration would be gladly accepted.
