No way I know of, but if you figure something out - please share....
According to second issue, there is a way to make a shortcut on Lightroom sdk manual on page 34.But i can't find a way to make a button as you see the flickr button on lightroom 3.0
I hope Adobe provides a ready way to do this in Lr4 SDK.
But you may be able to think of something clever.
I used "hot metadata" in DevAdjust, but that's only available in library panel.
I can think of some ways that might work, but you probably wouldn't like them, and neither would your users, e.g.
- a mock collection that acts like a button, together with a background task that keeps checking if its been selected...
Right now I don't have something clever on my mind, but yes, I hope this is a way easier in sdk 4.