i worked on the script

(the "dots" in the screenshot are placeholder for tiles not added yet)

+ it don't use the active vertex, it uses all selected now

+ it joins all added parts to an object

+ it uses objects by it's names

- a bit slow when big meshes (but better than putting each extra)

- error when object missing or on inactive layer

i added 5 sample-parts (rest to do)

also to do:

random parts (for example for the top side)

put it into blenders ui (like addon, at the moment only script)

import funktion (only when not too slow)

complete tileset (for testing)