Hey all, first time poster in need of some assistance. I've been following the Hand-Drawn Mapping (for the Artistically Challenged) guide and everything was going fairly smoothly until I ran into an issue with the Layer Cleanup step. I delete the colored terrain layers, order the layers as mentioned, but when I show all the layers except rivers, base, and background this happens -- specifically when I hide the background:

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The mountains, hills, and trees brushes I placed on the map disappear along with the background. I can't figure out what I may be doing wrong for the life of me. Thanks in advance!