How to place flats from other wads into yours on slade?

[Leon]

I'm having trouble. I have been able to transport the other textures but flats don't work. I copy them, place them in my wad under the FF_START and FF_END entries and then add them to textures. Am I doing it wrong?

[GreyGhost]

There's no need to add them to textures, though if they're looking wrong in-game they might need converting. Multi-select the flats, click on "Convert Gfx To...", select "Doom Flat (Paletted)" from the Convert to: list, untick "Enable Transparency" and click on "Convert All".

Check that they're between FF_START/FF_END instead of under them.