The REIF app works as an Excel model, though without the ribbon. However, it still retains much of the functionality through keyboard shortcuts:
Formula Bar = Ctrl + F2
Page Break Adjust= Click "Page Break Preview" Icon at Bottom
Print = Crtl + P
Save = Ctrl + S
Important: when saving your model do NOT change the file location otherwise the launch screen will not show the model
Redo = Ctrl + Y
Undo = Ctrl + Z