HI mikes,
Merge to Panorama is an option only available with PHo, not with PSE (and has always been).
To compose a Pano in PSE, you can do the following:
- Select several photos in LR
- Edit in Adobe Photoshop Elements
- In PSE, File/New/Photomerge Panorama
- Save Pano
- Close PSE
- Import saved Pano into LR
Regards
Sarika