Last year, I made a very simple mod that basically added new versions of the bow you make at the beginning of the game (this one here: "Primitive Archery" http://community.playstarbound.com/resources/primitive-archery-1-0.4200/) Long story short, I uninstalled Starbound and haven't touched it til now. How difficult is it to update my mod for 1.3? Do I even need to update it at all? I should note, it doesn't replace anything. It adds three (or four? Can't remember) new bows based off the hunting bow, with different colored arrows.
When was it? What version Starbound was when you made your mod? Probably something changed in file systematization since then. Just compare your bow with 1.3 version bow.
If you need help, just pm me. But as he said, comparing your bows to the vanilla bow should be all you need to do.