The General order of scenery is basically the same: well more or less, no matter what sim well should say this applies to FSX or P3D which are the most common at present. (Can't speak to X-plane or others).
From the top down in your scenery order: should look something like this: (When you add scenery verify the order is correct from the bottom up (and you have to set the FTX Insertion points.)
TOP
3rd party addon scenery IE: RTMM addon and below it RTMM libs (etc)
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FTX
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Tongass Higher
Tongass Lower
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Open LC
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"Named" default scenery bases/entries (Continents/Cities etc)
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Mesh
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FTX Vector Entries (EXX, CVX, APT, FixedAPT, OBJ)
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"Numbered" default scenery bases/entries (0000 Base - 1107 Base)
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FTX Vector Entry (AEC)
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Default Scenery (BASE)
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Default Terrain (World)
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Bottom
So first check your order and your FTX insertion points and correct if needed and try it again.
If still not a correct display, turn off Black Marble, Turn off mesh.. and try it again to see if the elevations are correct.
Norm