Italian for 'backtrack', Tornate is a small mappack that consists of 4 maps. Each map at one point was an editor map, then the maps were totally redone in Hammer. Tornate also gives the Portal 2 artstyle a twist, adding blue tiles in contrast along with lighter metal tiles.

These maps are more on the easy side, but who knows, I can't really tell you the difficulty. I don't know how you think with Portals.