That's something I'm a little curious about. Why does it take so much memory to house? Granted, it's a far cry from the likes of say... Farcry, but I mean, Street Fighter x Mega Man was about double the size of either of the Wii games, but this is ten times the size of that! Rockman 7/8 FC were a little bigger than the Wii games, as was Day in the Limelight 2. Both the modern SuperDanny games are around that size, too. In contrast, Perfect Harmony's most recent version is about 105 MB in size, but it has an assload of content, huge sprites, ridiculously complex backgrounds, and lots of non-8-bit special effects.
As far as the topical game goes, the main culprit here appears to tbe the "levelart" file, which weighs in at 132 MB. Why? "guns" (which I assume is either just the player weapons, or all projectiles for all active sprites) comes in at 78 MB. "cutscenes", "gameobjects", and "menus" of all things are all over 10 MB in size as well. The other three files, "cutscenedefs", "levels", and "misc", are all under 1 MB.
So my question here is, why is this game, which should be roughly the length of Mega Man 4-6 (at a guess), so damn big in file size? Even if everything except the music was left as raw assets (GIFs, PNGs, etc.), I genuinely can't imagine how it could possibly be that big. Did you leave the music and sound effects as full, uncompressed 16-bit 44.1 Khz sampling quality WAVs or something? I almost want to say that would be justifiable in case this game was picked up commercially... but I'm pretty sure that Ogg format doesn't require a commercial license to use in profitable projects and it's just as efficient at WAV, but much, much smaller.