How would I add npcs to the overworld with their own custom scripts and text.

[Wazadude]

So I know how to add npcs to the overworld and make them use a pre existing script in the same script file. However I want to make a custom script for my custom npc so I can get them to give an item. The problem is that when I write a new script for my npc and link it to the same text file as the rest of the present npcs I get a weird bug. The game loads fine and I can enter the house with my custom npc but whenever I enter the house the camera weirdly shifts and only focuses on the top left corner of the area and I can't see my character because of this and I'm pretty sure I get locked in place. Any suggestions to implement a custom script without bugs occurring.