Nah it's not the first - someone else made a mod that has a "gold cheat" where Dengler the innkeeper gives you 500gp, but this would be the first one where someone actually modified the source code and posted it publicly. That was by simply modifying the conversation files.
Liston made his own mod with some stuff in it and told me what he used to do it, and then I made this one.
People used their keyboard to move items in the IE games o_O
Don't know, but I think that would require modifying the item format in the code, and then the item files themselves. Might be trickier.