So Bionic, I downloaded your recent version, and I can't find the Sword in grasstown. Also, I'm just gonna give a small bit of feedback here
-The Current Enemy robot sprite looks, uh, "unfinished" to put it nicely. The colors seem to clash, not in a good way.
-Grasstown seems empty, and I'm just gonna put this out there, in the original Cave Story, you can see that there are some parts of Grasstown that seem decayed and broken. So unless grass town is just being built in this mod, maybe add some buildings or blocks or whatever to make the place seem, not boring.
So yeah, I haven't goten far in the rest of the mod, but good luck.