In my workflow, I import - select - keyword - retouch - rename - and convert .nef photos to .dng. Then I archive all images. 

If then I retouch again my dng in the develop module, do I need to 'Ctrl+S' (Save metadata to file) or is it done automatically by Lightroom?

Let's say I [retouch -> convert to dng -> retouch] an image and then send it (but not the catalog) to someone who has Photoshop, will he have the last version of the dng or the version at the time I converted the raw to dng?

Maybe someone who has Photosop could try?

Thank you.