YOU ARE THE MAN!!!
I am updating it right now and will replace the old cover in a few minutes. Thank you VERY much!
If you're feeling really inclined you could always do the shots for the 2nd zelda too 
No worries, just glad I could help! I tried to get them as pixel-perfect as possible to the originals (minus the font and sprite change, of course) but with the blurry screenshots that's kinda impossible so I got as close as I could. Besides, it gave me an excuse to play through (at least half of) the game again so it's all good!

And no problem about the Zelda 2 screenshots either. Those look pretty simple to do. I'll get to it after I eat.
Edit: Was actually quicker than I thought:

Not sure if the second screenshot (the one in town) is meant to be in one of the purple-skied towns or if the box background was just recoloured when scanned, but given Link's stats I'd say it's in the second screen in Rauru so that's where I went. Also never noticed the black borders on the map screen until now, but those'll get cropped anyway.