[Dragon]

Background bitmaps go into effects folder, skybox maps go into maps folder. Your planet will go to effects unless used on a skybox (which is not the case).

[Deadly in a Shadow]

Ok for the first time, but if you are planning on releasing your work in a mod somewhere down the line you'll need to learn how to use tbm's, using stars.tbl is not ideal.

BTW: Shouldn't the dds files go into the maps folder?

I think they go into effects folder, maps is for model textures IIRC.

I already use an str-tbm. I want to implement them into a campaign.

[Rodo]

I already use an str-tbm. I want to implement them into a campaign.

then you are on the right track