Rumian Land is a pretty standard 2009 platformer with multiple worlds and bosses to fight through.
Since I had a similar issue with an impossible level in Rumian Land like in Eiya Gensoukairou, here's a fix for a level that kept looping around with its warps.
Here This goes in the Data folder
This fixes a loop in 4-2. I don't believe there was another way to finish the level in the rest of the screens and warps available.