So, it can take over creations (trucks, tractors, etc.) and/or throw them, and/or manifest within the confines of a creative work, or in the blank, unwritten spaces within that world.

Why am I suddenly thinking of trapping it in a mad-lib?

Or have a mad-lib as part of the plot?

I would question how it manifests in artwork, or sculpture - is it able to put on the form of a painting or sculpture as a form of Taken? Does it essentially commission these monsters as creative works at first, to manifest them in the world?

Hieronymus Bosch comes to mind... as any number of other persons tormented by visions. Appearing in nightmares, maybe people take these visions and put them down in some form to trap them in the real world, remove some of their power (putting them to a solid form rather than a nebulous, unquantifiable presence in the mind) - but unknowingly (by trying to limit a dark presence) provide it with a scaffold to the real world...