Where is this file referenced? I notice it has all the techtree limits for all the sizes, but can't figure where these are used.

BTW: Can I label issues as questions etc, or only you?

Hmm... pretty sure that file is deprecated and not used anymore. Should be able to be safely removed.

Pretty sure only repository admins can flag questions/etc (owners, authorized contributors).

Removing the file in dev repo; don't worry about a PR/etc.

OK, thanks. I did not see any interference from it while changing the upgrade paths, so was wondering about it's function and possible problems it may cause. I can try to delete it here and see what happens.

Should be safe to delete -- all of the tech limits stuff has moved to the stock PartUpgrade system. I think the file was just left there for reference, and then forgotten about :)