Wind Sword Cinemap Glitch

[Silent Mercenary]

I was testing magic sword animations in FE7 last week and decided to add the Wind Sword to Marcus' Peak's inventory just to see description display limits. I know the Wind Sword is always kind of glitchy, but it usually just added some black-and-pink codebars to the word <Items> when you check its description. But that time, it first created an Eliwood clone floating in the mountain range that impeded real!Eliwood's actions (forgot to screenshot), and then it did the following, which I have named the Cinemap glitch:

It makes the background image (the map/building cg) scroll from right to left, although the terrain tiles stay the same and the fog in the scrolling map changes according to unit movement like normal (except for the glitchy first/0 column). Has anyone else had a similar error and is this glitch based on the game's inability to display the complete Wind Sword description or something else about it? Also, is there a way to make the glitch purposely happen? This would be interesting for a raging rapids effect on a Battle in the high seas map, a GBA version of "On Drifting Clouds" or another crazy map idea.

And while I'm at it (to not make another topic until next month), can someone direct me to a good tutorial for SNES Palette Editor or a similar utility?