ID:1437898
 
Place map object -> use Shift + north/south/east/west -> after everything's nudged, convert the map to a .dm file
and replace all instances of "step_x" and "step_y" with "pixel_x" and "pixel_y" -> change it back to a .dmm file.

Replace the .dmm in the file name with .dm

Dreammaker may not update it though for it to be used as such
(doesn't for me, most of the time),
so you'll probably have to close it and reopen it after renaming it (both times).
You don't have to rename it, just open it in notepad.