Map03 requires the Doom 2 wad; this map cannot be opened using only Doom 1. Map03 is in Boom format.
Map04 requires Freedoom Phase 2, a second installment of a libre Doom title. I'll link the Freedoom website here: (https://freedoom.github.io/download.html). Map04 is in Doom 2 format.
I tested both of these maps using the UZDoom source port. These maps have no specific difficulty differences. No matter the difficulty, they all have the same layout.
I uploaded my maps as a zip file it should be attached to this post.
To access the levels quicker in-game, use the backtick key, usually located to the left of the "1" key, and then type "map" followed by the map's ID, like "map map03," which accesses the third level. Map03 is the third level in Doom 2, and Map04 is the fourth level in Freedoom Phase 2.
I appreciate any feedback given, and I'll incorporate that feedback in future levels I create.
Thank you for reading and/or downloading