New to hacking, need advice

In FF3usME's sprite editor, there's a checkbox for 'New sprite sheet format'. Are you getting this error for FF3se then? Try importing the sprite with FF3usME. But the error said it does not support interlaced sprites, and you said you interlaced yours in? Sounds like that's not permitted maybe, I'm a spriting noob and have no idea what interlace means, but I know if you don't edit your sprites in the editors themselves there usually is issues re-importing them, like if you use another program to edit them.