Yes, when I first did this room, I didn't realize those were platforms either.
The method I used to solve this room was:
Click here to view the secret text
×1. I took a screenshot of the room (duh!)
Click here to view the secret text
×2. I used a paint program, and crossed out all of the arrows I didn't want the roaches to travel over.
Click here to view the secret text
×3. The easiest arrows to cross out are the ones that lead to Black Holes (all arrows point inward) and White Holes (all arrows point outward). Then just repeat this step each time you eliminate a square.
Click here to view the secret text
×4. With a small exception, the roaches can only move Left and towards the middle row.
____________________________
Casebier
--------------------------------
Revisiting old Project: ZelDROD 1 / ZelDROD RPG (If I can ever find the custom graphic files that I made for it.)