Help with making DLCs for a VX Ace Game?

So basically, I need a tutorial in how to make this possible without revising the whole game again into different versions (ie, 1.0, 1.1, 1.2...). I know how to make DLCs if it is a planned DLC (meaning you are sure that you'll be making it as a DLC and not an in-game feature) but what if it isn't? Like the game is done and you already uploaded it then you just came up with an idea let's say after a month to add this certain thing to the game but don't want to edit the whole game again?

I believe that can be achieved with this.

I think that's only for Maps, Events and Tilesets. Another thing is that I'm not asking for patch DLCs, I'm asking for stand alone DLCs (which are Plug-and-Play where the player just copies the file to the game folder and bam, it's in the game.

It seems that people have managed to use it for DLCs, so I'd look a bit more into it. Especially since it seems to be the only script allowing you to make one.

I really don't see how this can be done. (That script might work.)

If you add a map later, the game won't know to send the player there. If you place an event that sends the player to the DLC map, before you make it, then it'll error.

Wait... I think I have an idea.

Map A sends you to map B
Map B is empty (It then sends you back to map A)

When you add the DLC: Map B is now the DLC.

Map A sends you to map B
Map B sends you to Map C
Map ETC send you to ETC

Yeah but that's for maps. But what if it's characters, events (like in-game dialogues not common events) and the like?