@ Hobgoblin - Glad to hear you dig the screens. Yeah, I didn't like a lot of the official ones so I thought to make my own. While I'm unable to take requests at this time (due to preparing mods), you should know that Quicksilver is on the list, as I didn't like his current one either. More screens are coming soon, including Hellstrom, Black Bolt, Pete Wisdom, a better one for Shadowcat, Enchantress, Witchblade (the next mod I'm doing), and more.
As for .igt, nah it's not important. Your game will work fine without them. None of my screens use an .igt, and they came out fine. As far as I can tell, there's no difference between those that do and don't. I don't delete them (just in case), but they're really not needed at all.
