LAndromada

One thing I really hate in open world RPGs is when the game decides to remove NPCs from the world for no apparent reason. I started playing DD not too long ago and for now I noticed 3 NPCs affected by this issue: Jaquan, Rojay and Grecio. I haven't progressed too much in the story for now but according to reports I've read they don't ever come back unless you start a new game. My knowledge of modding is very limited but I would still like to try and fix this issue. So does anyone know which files I should modify to make specific NPCs persist in the world? I tried looking into npc037.arc to start, the problem I have now is that I have no clue what programs I should use to open most of the files located inside .arc files. I also tried to look through the "stage" and "quest" folders, but I ran into the same roadblocks. Any help would be appreciated.