Expression cannot be evaluated? (Archetti hitboxes)

I've implemented Davide Archetti's Hitbox resource as part of something I'm doing with BasicShape (a simple class I created, think of TSStatic with datablocks and processTick). When the datablock' preload function is called, I find the HB## objects as the resource states to. When preload is finished, both times it runs (one with bool server = true and one with false), the HBIndex array is full of -1 (my model doesn't have hitboxes, only a normal collision mesh - I just wanted to find out if the class worked). However, when I fire a projectile at the object, Torque breaks and takes me to castRay on my new class. One line evaluates the HBIndex array, and all its elements are now CXX0030: Error: Expression cannot be evaluated.

What does this mean? It seems like something's come and tampered with my datablock values after they were preloaded, but what? Or am I missing the point of what the error means?