Those models are quite large - 12MB each, and even the scene editor was struggling on my laptop (8GB ram).
From this link, it’s hard sounds like it’s difficult to multiple sprites that exceed a size of 2000x2000 (around 15MB).
Given you’ve got around 30 of these 12MB models in the scene, you may be expecting too much and pushing the limits of GDevelop.
But I’m speculating. Someone with better knowledge of GDevelop internals may be able to give a more definitive answer.