It sounds like you're experiencing some trouble with uploading your .rplib file as a forum attachment. We haven't decreased the forum upload limit, so we'd expect that you'd still be able to upload an .rplib file of that size.
That said, I was hoping you could provide some more details about the issue you're running into. What happens when you try uploading your .rplib file as a forum attachment? Are you seeing any error messages? Any additional information you can provide may be useful as well. I'll be standing by!