I think I see the problem.  When you purchase a Suite license its a single "Suite" license, not 1 AutoCAD LT + 1 Revit LT + 1 [whatever].  If you run multiple products (of the same version) at the same time, it only pulls that one single license.  In order to cross-grade you'd need a specific AutoCAD LT license.

For what its worth, with all the other Windows dependant software included in the Suite I'd just bootcamp the hardware and be done with it.

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If you are going to fly by the seat of your pants, expect friction burns.
"I don't know" is the beginning of knowledge, not the end.