Having read Nicholas of Cusa’s De docta ignorantia, I think the biggest problem with his entire system is the completely superfluous Aristotelian element that is nothing but an accretion to an otherwise immaculate Platonic metaphysics.* In the first few books, Cusa paints a wonderful vision of the explicatio, the unfolding of that which is enfolded in the unknowable and trascendent God. God is said to “contract” himself in finite being, but there are stages to this contraction. The first contraction, so to speak, is that of the contractum universum (“the contracted whole” or “universe”). It is the contracted maximum of God’s uncontracted or absolute maximum. It is the whole as finite and contracted, most adequately expressing the divine uncontracted infinity. It mediates between God and the rest of the finite world.
Then at the end of book two or three, if my memory is serving me, almost out of nowhere, in a manner completely inconsistent with the argumentation that precedes, he tells us that the contractum universum exists only as contracted in particular things, i.e., in primary substances, as Aristotle puts it. In other words, the contractum universum has no independent subsistence, not only from God — which of course would be an acceptable qualification — but from primary substances comprehended under the contracted universum from a cosmological point of view.
This flattening out of the platonic hierarchy by deflating the mediating terms is a common move amongst some scholastics, from whom Cusanus almost certainly imbibed such an idea. You can take Thomas Aquinas’ understanding of the divine ideas as an example of this, where the ideas are conceived of as mere modes according to which the divine essence is imitable by rational creatures, which while true as far as it goes, is not all that divine ideas or forms are.
*I do apologize for pitting Aristotle and Plato against one another, as I believe they are mostly in accord with one another, and I otherwise dislike the imagined polemic against the two, though there are a few differences.