Gerald,
a very simple way of doing so would be to place the whole Manipulate[]
in a new extra notebook, i.e.:
CreateDocument[Manipulate[t,
Control[{{ lt, -20, "Start Temperature", ImageSize -> Tiny}, -40.0,
240.0, 10.0, ImageSize -> Tiny, Appearance -> "Labeled",
ControlPlacement -> Left}],
Control[{{ incr, 10, "Temp Increment", ImageSize -> Tiny}, 1, 50.0,
10.0, ImageSize -> Tiny, Appearance -> "Labeled",
ControlPlacement -> Left}],
Control[{{ ut, 120, "End Temp.", ImageSize -> Tiny}, -40.0, 240.0,
10.0, ImageSize -> Tiny, Appearance -> "Labeled",
ControlPlacement -> Left}],
Control@{{t, {}, ""},Table[loadcase -> ToString[loadcase] <> " deg C", {loadcase, lt, ut,
incr}], ControlType -> CheckboxBar, Appearance -> ("Vertical"),
ControlPlacement -> Bottom, Appearance -> "Labeled"}],
WindowTitle -> "Please Input Values", WindowSize -> All];
Does that fit your needs? Regards -- Henrik