I wanted to work on a new artbot design using Sketchup on my MacBookPro, but immediately ran into a hangup. Sketchup is the third program I've run into that has problems running under the Mac Lion OSX. Thankfully, the Google Sketchup website (link below) lists all the known issue and suggested work-arounds. Hopefully they will be resolved soon. Otherwise I'll have to power up my old WindDoze system, which I really don't want to do just for this one small project.