Hello, I don't seem to be able to load the .dat files from single player
mode that I "Dump"(save). Is there any way to load the .dat files in
the client, as single player, or am I required to host my own server for
myself in multiplayer to be able to load a file for me to play on?

For instance, I want to play and save a file I can continue working on later by loading it.

Single player Saving/Loading would be nice since I don't have access to the router's page for port forwarding.