Help! Custom Models

[Purplemint]

So, i published a Cookie Run/Cookie Run Ovenbreak Customs section, but it got rejected. The last line in the "Following Reasons" said this: "Don't make game sections if you have no intention on submitting anything...". Well, i AM going to submit it when i will have Windows 10, via 3D Paint, but i don't know if it's allowed to submit 3D Paint models, since i don't know how to use other programs.

[rveyrand]

if you want to create a new section, you need to upload a model with textures, else moderators won't accept seeing empty space.

also, required file format are the following:
-OpenCollada (.dae) [if your creation has rigging; animations; etc]
-Wavefront .obj + .mtl file
You can, after, add custom format (.blend; .smd etc).
last note: textures must be either PNG files or jpeg files (no idea about .tga or .dds tho)