Advance Map - warp tiles lead to black screens

[kangaloon]

Hi all,

I've made very tiny rom hacks in the past using pokemon essentials but now I'm expanding to more advanced stuff. Anyways, I'm working with Li Yun's emerald base which is great and I'm doing some map editing in advance map.

I have no issues creating my own maps, placing events, etc, but whenever I put a warp to a new map and test it in VBA it always leads to a black screen.

In this example, I've replaced Littleroot Town (0,9) with a custom map. All warps out of houses direct to 0,9 and basically everything SHOULD be working as normal... clicking the warp tiles in A-Map leads to the places they should. Yes I made sure to insert/replace the original map and register it as 0,9 too.

Any ideas on how to fix this? Is there a way to double check it in XSE or a hex editor?

Thank you for help :)

Spoiler:

The warp here leads to 1,0 (May's room)

And from inside the house, which I made the player's starting location, the door is directed to 0,9

So this should work right?

EDIT: So the warp works correctly when I use mGBA, but upon leaving the house I get stuck in a textbox loop that pops up and says "This is a test message. This is a signpost" With no way to stop it.