I've been wanting to report those for a while, but only got around to it now.
Akumajou Special - Boku Dracula-kun (NES)
The bottom of the screen shakes constantly at the dancing girls minigame.
Savestate to get to the minigame quickly (just press A):
Lagrange Point (NES)
Similar to Dracula-kun, the bottom of the battle screen shakes constantly.
Megami Tensei II - Digital Devil Story (NES)
In the battle screen, there's a graphic glitch below "AUTO".
SD Keiji - Blader (NES)
This is a strange one. During the intro, there are two characters exchanging dialogue. In neshawk, they look like this:
But in Mesen, they look completely different:
Since I don't have real hardware to test, I'm not sure which one is correct.
Necros no Yousai (PCE)
Game crashes during the intro, making it unplayable.
None of the first 3 bugs exist in Mesen, and Necros no Yousai is playable in mednafen.