Was thinking the same - tried finding it everywhere but couldn't locate it. The large map in the default game is still tiny compared to what the super map size enabled. Does anyone remember the author of the mod?

No Answer? you can't give us something awesome and then take it away

You can edit a file and get huge map size.
Look under Guides...

If this mod is not going to be uploaded again, I would like to know how to load saved data using this mod.

You would not mean this: "Bigger Map Size" from the workshop

Recent versions of the game seem to be able to load mods even if the mods used in the save data are not present.