Novum11: Does gog have a game pad program for games that don't support it?
There isn't, but
let me map the keys to their [url=http://terraria.gamepedia.com/Game_controls]equivalent buttons on the Xbox controller. I just went down the list with the program open and assigned them.
Once you've done that and saved the configuration, keep Antimicro open, then start Terraria.
Recommendations:
Toggle Smart Cursor on, it's so much faster.
There's a preset for making the Right Stick behave like a mouse.
The shoulder buttons were a bit too sensitive to work as Mouse Scroll Up/Down. I might change to using the D-pad.
Right Trigger feels plain weird for left-click.