Interacting with HUD leads to glitch screen

I'm new at NESmaker, going through the tutorial videos. In the platformer games I've made, when the player jumps and touches the HUD, the screen changes and becomes a black screen filled with 0s and 1s, where the player character is stuck. This also happens on my adventure game when changing over to certain screens, and I'm racking my mind trying to figure out why. I've tried to follow Joe's tutorials exactly as he does them - what am I missing that the player keeps warping to this screen?

You've simply entered an area where a screen doesn't exist. Either you need to block access with solid tiles, or set up the new screen in the overworld editor.

I've tried placing solid blocks in the HUD area, but it still triggers the empty screen glitch when the player character so much as touches the HUD. I could place solid blocks in the layer below the HUD, but this significantly limits some game design aspects (i.e. looks odd when the player character jumps into an empty solid space well below the HUD.) Is there any workaround to this, besides just creating a new screen above it? Also, I had an adventure type demo where it was triggering this same glitch when I walked into a screen I had already created. However, I can't replicate it now, because the game won't even load in an emulator anymore - maybe the file got corrupted or something, I don't know. It was just a demo, so it's no big deal, but I'd like to learn how to avoid this "empty screen" phenomenon in general.

A trick could be to make your playable area overlapping the HUD area (1 row overlap) and fill that row with solid tiles in ALL your screen ...