I'm not entirely sure myself. If I can figure out how to edit bumpmaps without making them look like garbage, I might make the ice just a bright blue, shiny, icey-ish version of the main tiles, I dunno.
I don't really remember CaveStory having an "icy" world, so I think that's the only possible texture for the Ice Caves. Are you using any normal map generator? There possibly are some free ones that can give satisfactory results (or maybe not; I'm just an idiot).
I'm considering it, yeah. Same for Damsel. Though I don't know yet. Making it look right will take some work, for sure.
The shadow might look a bit weird, but you can turn it off. Making an entirely new sprite-sheet for a character is definitely going to take some time. Then there's the three damsels. Pug should be a mimiga.
Yeah I made the Pug and Damsel player mods when modding first became a thing. It's been awhile since then, cool that you remember me though!
Yeah, I remember many of the names of that time. That was probably one of the times Mossmouth was active. Then everybody lost interest, the forum drama drove the remaining away, the spam bots ruled this place till Derek got informed, and now the place is similar to a graveyard. And sadly, Derek said he probably won't make another game (of the level of Spelunky) till 4 years. So there we go, Mossmouth's funeral.