HaloMods "Classic" Read-only Archive

When I click Save in the meta editor, everything I've changed resets back to what it was before I saved. I can't clone chunks either, without getting that Non-Negative error.

I'm guessing this is a problem with my .NET Framework, so can I get some clarification on what version(s) I need? (and perhaps a link)

Thank you in advance.

You might just need to download a different Entity. I've had little problems like that before, and all I had to do was get a different Entity.

Well, not only is it happening with all versions of Entity, but I'm using 1.3, which I've never had problems with.