That's simply not an option if a customer comes to us in a panic that they're going to miss an important deadline because their project is corrupt. In that situation we will obviously do anything we can to help regardless of what they used in their project. But we want to take steps to prevent this in the first place. Other than that, we already don't offer any official support for any third-party addons of any kind, but even then I think it's irresponsible to allow users to get entangled in difficult compatibility problems and shrug it off with "sorry, we don't support that" - we'll still take steps to try to prevent that in the first place.
I'd add that as far as I'm aware, no other software on the market allows third-party developers to copy-and-paste all the official features to tweak and re-publish them, because it's fundamentally a terrible idea. It violates the "don't repeat yourself" (DRY) engineering principle and causes ongoing compatibility problems as each copy of the feature has to be maintained in parallel to the changes made in the official version, but inevitably isn't maintained, or is done incorrectly and adds bugs. This was basically a big mistake made in the early days of C2 when we were literally coding on our laptops in our bedrooms doing whatever we can to get the company off the ground. Now we're trying to reverse that mistake, which can cause some awkwardness in the short term, but is absolutely the right thing to do.