Most of the Japanese players and also Nicovideo users most likely beat the game with no problem. Sure I can't beat it either but I've plan to write a walkthrough on Rockman DEM. I've also wrote a Datacrystal wiki about the game but I need a little more research on it.
I did mangage to beat Flashman's level first, but I can't past Metal man's level. Even I do reach him, there's not even a single weapon energy left to weaken it since I used it during a level.
Yeah, I kinda found DEM by luck because MISTY hosted it on the Japanese 2ch boards. And added some new patches when I opened the ZIP file.
I hope the next one, RM2 Gensokyo won't be hard as the others.