You're supposed to insert it with GPS
, not Asar. The latter is for game-changing patches.
Paste it to the blocks folder, open the map16 editor and drop the tile you want in any page (in that case, tile 12F). Let's say the tile is tile 200 but you want it to act like tile 130 (cement block) - open list.txt and do as follows:
Save the text file and open GPS. Just type in the ROM's name as soon as the window appears.