Gnats 4586: Invalid model file saved when Output Device Record edit dialog 
 is open ("_RWSAVED" error).

Model-1 (Source):  bug4586-1.mdl.gz
Model-2 (Resaved): bug4586-2.mdl.gz (NOT LOADABLE).

Difference:
 1: set plotpage "$ws.outputDeviceMgr.PlotPageInfo.Plot Page00000"
 2: set plotpage "$ws.outputDeviceMgr.PlotPageInfo.Plot Page00000_RWSAVED"

Model 2 was produced from Model 1 with the following procedure:

(1) Load Model 1 (bug4586-1.mdl.gz)

(2) [Workspace]: Utilities >> Output Management ...

(3) [Output Manager]: Select Plot Page00000 (Plot Page)

(4) [Output Manager]: Click "Edit..." Button

(5) [Plot Page: Plot Page00000]: change "Output Name" (add "Change 1").
 ... BUT DO NOT CLICK the "Modify" Button.

(6) [Workspace]: File >> Save As... 

(7) [Save Model File As...]: bug4586-2.mdl.gz
 ... this creates an INVALID model file.

(8) [Workspace]: File >> Reopen Model >> ... bug4586-2.mdl.gz
... ERROR REPORTED:

   Load File Error
   invalid command name "RiverWare
   Workspace.outputDeviceMgr.PlotPageInfo.Plot Page00000_RWSAVED.

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