Hello, I am Polargames, Feel free to call me Polar.
To answer your post about msu1 SMW. Did you make sure that all of the necessary files are named right? Sometimes a small typo can make it not work well.
Now if everything is named right and the game does work. It sounds like it might be a minor error in the MSU1 code. To fix that you would need to get the newest version of the patch.
There is a small chance that it could be the sd2snes and the super NT, but I have seen a lot of youtube videos and read a lot of forum posts that it plays well, So I am not to concern about the hardware.
I hope the info helps you out. :-)