It's complicated to use in Forge - I don't even completely know how it works. Moving an object's spawn in Sandbox was a lot easier, but I haven't gotten the program to work in a while.
I've been planning on doing some research and testing to learn more about the spawn coordinates and "chunks" in Forge. James Sharpshooter also held an interest in object spawn coordinates. He talked about a "Map Object Placement Editor" in his AIO Thread, but I think he gave up... Shame, I guess I'll be doing this on my own.