Sooo... here's a few tidbits on tile crafting I thought I would share.
To keep your floor tiles in their place, you might try placing them on these non-slip shelf liners. They are cheap and should keep things from sliding around. However they do have a thickness to them so you probably don't want to use them on decorations you stack on top of your tiles. For that I recommend...
Static Cling Vinyl
You can pick this up at a Joann's or an Aaron Brothers. Basically it's just like the stuff they put over the screens of new phones to protect them. You know, that plastic sheet that seems to hold on to any smooth surface without using glue? So if you have laminated or con-tac covered surfaces to your maps, you can glue some of this static cling vinyl to the bottoms of your decorations and they shouldn't slide.