Here are my blocks for this week:
GrannyQ - After you crop, click on Export. Move the Image Size to 640 pixels. Click Export again and notice where it is going to be saved. (I've had trouble with this also.) Mine saves the export at Picasa>Export>Desktop. I hit the diminish (-) at top of page to keep it open, that will make it easier to find. Once you start using the file, Picasa will automatically go there to retrieve your photo. Hope this makes sense!