Adelaide Software International (and the parent company Delphine ) are long, long gone, and maybe Doki Denki bought their assets but Doki Denki went bankrupt in 2004. Wikipedia says LBA was published on Steam by "DotEmu", but DotEmu were bought-out by Focus Entertainment in Aug 2021, and Steam currently says the publisher/developer of LBA is "[2.21]". Huh.
Viewing post in Twinsen's Little Big Adventure Classic comments
This is a blog post from Didier Chanfray, one of the co-founders of Adeline Software International. He talks about the current state of LBA.
It sounds like they're building up to doing a remaster of this game and possibly LBA2 if the first one goes well.
https://twinsenslittlebigadventure.com/a-message-from-didier-chanfray/