Hi...I'm building a dialog with inside a flow diagram representig various components of a system and its status...something link this:

I've used label widget to make the boxes and line widget to make the connections between boxes....The colors of the boxes must change according with the status of the particular component of the system.
Well, I done this but now I have a problem...I can't resize the whole diagram because I can't use layers. Using layers I lose the right aspect of the diagram.
How I can do this? There is a manner to view the whole diagram (all boxe + lines) like a unique thing so I can use layers? Other solutions to make this diagram?
Thanks