THIS JUST IN
I went back to the effect I’d been working on the previous week, and, on a whim, decided to change the vertex shader and pixel shader target versions. Apprently it works properly if the techniques compile to different target versions. O.o I’d been compiling to vs_2_0 all along; if I change ONE of the techniques to vs_3_0, then it works, but if I change two to vs_3_0, then the second of which doesn’t work again. I wonder if that will help to trace the error…?
I hate to pester, but, any updates on this? I’m reluctant to continue working on this project as long as this error persists. I added some additional information in the github thread https://github.com/mono/MonoGame/issues/4909.
I found the root of the problem; whomever it may concern, please take a look at it in the thread linked above.
Hey @ed022, in case you check this before GitHub, I set up a PR with the fix following your suggestion. Sorry for the incredible slowness and thanks for the help