RM2K - INVALID TERRAIN ERROR ON WATER

Whenever the player character using noclip or an event with Through ON moves on a water tile, I get this "Invalid Terrain" error and then closes the game. I don't recall this happening when I worked in RM2K some years ago, but back then I was using the illegal version, while now I've moved on to using the legal version. Is there anything I can do to make events move over water without this error occurring?

Oh. I had gotten rid of the terrain entries in the database because I didn't think they were used for anything in my game, lol. Created a bunch of empty ones, and the error doesn't show up anymore. Thanks.