The only work-around for an 4.26 projected updated from a previous version was to use a side project as I mentioned and then migrate. Unless anyone else has any bright ideas? Did you find any other solution? Unfortunately, no. As a workaround, we're going to start a blank 4.26 project to work the characters, and then use the UE4 migrate tool to bring them into over to our main project which is already in mid-development. Which seems off to me, but that's what they said so there must be a reason. Will wait and update here once I find a solution! UPDATE: Support's position on the matter is that the auto-setup plugin can only be installed in a new 4.26 project and will not work on an existing, already-in-progress 4.26 project. The update is only a day old, these things happen. I've got a support ticket in, but thought I'd comment here in case anyone else searching has an issue.

Uninstalling the update resolves the problem, and a fresh install still results in a compile error. Unfortunately, I'm having problems compiling our project after enabling the auto-setup plugin.

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