Is anyone able to attach a picture using Googles messenger app for SMS? When I click on the icon it brings up the camera but no way to attach an existing picture.
Yep. Once the camera is up look near the bottom (depending on the background it can be hidden) but there are little icons down there. The first one is camera (which it defaults to at first) then the second one takes you to your gallery.
Once you select this one it remembers the last choice (such as your Gallery).