There are three types of tilesets in the archive, BGOs and Mushroom Platforms. Everything can be used together except for tilesets - you can use only one tileset in one level, since all three use the same block IDs.
The archive also includes "tileset" files -they are used by PGE Editor to make your editing life easier. To use them, put graphics and "tileset" files into your level GFX folder, then open PGE Editor and open level that uses these graphics and "tileset" files.
Now let's look at all three tilesets!
Tileset #1:
Credit goes to:
Kopejo - he is the creator of these tilesets;
h2643 - for importing the tilesets to SMBX and creating PGE tileset boxes.