Update: Snails aren't very active, but didn't appear too terribly active at the store either (they were moving around but not a ton and were slow, despite having a submersible adjustable heater). The little one hasn't moved at all since I got them for the most part, when the body starts to out of the shell a little I try to put the snail upside right. Unfortunately due to how the shell is, I cannot get the snail sitting in an upright position, and have no idea if they, like nerite snails, can push themselves back upright like nerites can. My tanks are barebottom, maybe that's part of the problem or something. If they seem to discomforted after a few days I might have to take them back to the store (I know I probably wouldn't get refunded/credited unless the one person is there, but I want them to be comfortable).
I picked up two of them, an adult and a very small baby. They are eating what the fish don't eat (sinking pelleted fish food) and possibly algae, and the store has been carrying them for at least four months now with no losses. From what I'm reading, other Sulawesi snails eat blanched vegetables, fish leavings (partially eaten/uneaten fish food and even other things left behind sometimes but I'm guessing they only do that when food is scarce), and diatoms. I still haven't found any pictures of these guys online though, but I'm going to do what the store is doing and then some (by giving organic vegetables like zucchini and blanched chard), obviously heated and filtered cycled tank with some live plants (not sure if these guys eat live plants or not, I'm thinking not since the ones in the tank at the store weren't eaten).