Just posted new versions for SimpleExtManager, SimpleUndoClose and SimpleClear.
Whats new for all 3 extensions is the Alternate Toolbar Button. My answer to Jacob Holloway's review on the toolbar button blending into dark Chrome skins.
Updated in SimpleExtManager is the checking for state of the same extension in different groups. Now on disabling an extension group there will be checking to see if any of its extensions are also in another extension group and if the other extension group is enabled that shared extension will be enabled. Thanks to Brian Frichette for informing me on this one.