Shift and Drag copying should now work correctly. [This was one of those stupid little one line bugs that was so much fun to track down that I decided to spend a few hours on it)

Linking groups should now work better than it did, but still a bit of work to do on getting the rotations of all the parts after linking right. 
Added part of dalien's #301 patch (xml loading/saving related parts with some small changes)

OpenSim/Region/Environment/Scenes/Scene.cs

@@ -610,6 +610,8 @@ namespace OpenSim.Region.Environment.Scenes
                 {
                     SceneObjectGroup obj = new SceneObjectGroup(this,
                                 this.m_regionHandle, aPrimNode.OuterXml);
+                    //if we want this to be a import method then we need new uuids for the object to avoid any clashes
+                    //obj.RegenerateFullIDs(); 
                     AddEntity(obj);
                     primCount++;
                 }