Having prepared 50 photos of long Norfolk walk in Lightroom 3 I added location using Picasa after which Lightroom 3 reported them as corrupted! I could do no further editing in Develop mode but as I had completed this phase this was not a problem.
However Lightroom refusal to export them to their final destination was a problem causing me to lose all of my Development work.
My work methodology is to post process in Lightroom Develop, add keywords, rename with meaningful names and then switch to Picasa to add location, back to Lightroom to export to final file folder and upload better ones to Flickr. Although the photos appeared in index grid they were reported as corrupted. Looking at photos in Picasa the names and keywords all still OK but of course Picasa could not add Lightroom Development changes.
I had to open every photo in Photoshop CS5, do a small change so that I could save it, then Lightroom accepted it and would export the photos applying Lightroom edits. The small change was necessary otherwise CS5 ignored save. Important not to rotate any photo whilst in CS5 as Lightroom does not detect this and your beautiful sky graded filters are applied from the side!
I guess I will have to add location in Picasa before I start any Lightroom processing.
Does any know better way to add location in Lightroom.