May 05, 2011, 10:16:59 pm
Make sure you did not inadvertently lock the object in place. Go to your build mode, select the object menu, click the modify object button (three lines), select your object, click transformation, click lock position, click off. You should then be able to modify the object. If you hold Ctrl and window select a group of objects, or click modify selection, select similar; you then can modify a group at once using the above technique. Hope this helps.
edit: interestingly enough, the red box does not turn back to green, but will still allow you to edit/ delete. maybe a little bug there.