After compiling the projects and browsing Editor Log, I’ve found that about 80% of my project’s size constitute textures. The strange thing is that after I’ve lowered to minimum all my texture’s parameters, the file size didn’t change at all!
Would appreciate your help to solve this.
Did you make sure you hit apply? I’ve made that mistake 
Sure. I forgot to mention, that the problem is in particular with cubemaps. Is it true that cubemaps use uncompressed images and this can not be changed?
Because my cubemap consists of 2 primitive images (like white background, black stripe), This images are about 6kb is size. And the Editor Log says that my cubemap has 180mb of uncompressed size o___O
180mb would need to be some massively oversized texture given the content you have on it.
I’ve set Face Size to 128 for the cubemap. I’ve also set max size for every image to 256.And I still got those strange numbers.
I have tried a couple of things: reducing max size, format, but still I’ve got strange numbers.
For example my image has a size of 100kb, but Editor Log says that uncompressed size of this image is 4mb O_O. Where does this come from?