I copied these wall tiles from an RPG Maker VX tileset and arranged them to work for Engine 001.
How to use: In the Tile-Sets section of Engine 001, create a new "Lower Object" tileset and edit it. Copy/paste this onto and save. Have to create it this way to enable collision options (unless you create an actual wall under "Walls").
Also, I've added onto the default floor tiles with those from VX.
Screenshot of those tiles in use, with other modified VX tiles. (Lighting doesn't like these tiles very much. Place light objects with care.):
Hope this is of some use to someone.