See the attached example.
You need to make the SideManagerController the main controller:
Private Sub Application_Start (Nav As NavigationController)
'create a new navigation controller
Dim nc As NavigationController
nc.Initialize("nc")
NavControl = nc
Page1.Initialize("Page1")
Page1.Title = "Page 1"
Page1.RootPanel.Color = Colors.White
Page1.RootPanel.LoadLayout("1")
Dim lp As Page
lp.Initialize("lp")
lp.RootPanel.Color = Colors.Red
lp.RootPanel.LoadLayout("1")
Dim rp As Page
rp.Initialize("rp")
rp.RootPanel.Color = Colors.Green
rp.RootPanel.LoadLayout("1")
smc.Initialize(lp, nc, rp)
App.KeyController = smc
nc.ShowPage(Page1)
Page1.TopRightButtons = Array(smc.CreateBarButton("right"))
Page1.TopLeftButtons = Array(smc.CreateBarButton("left"))
End Sub
Note that we don't use the Nav parameter at all.