Bota
am i allowed to take a map, edit it and reupload it?
There is no official tos for mapping other, than letting mappers put their own licensing on their map or mention licensing their maps on ddnet.
If there is no licensing attached to the map(s) which is usual, then you can assume that ddnet's own terms of service doesnt enforce you to follow a non-licensing rule regarding the person who originally made it.