Hey all, I fixed this issue the other day. It took a little know-how, so I figured I’d write about it here in case anyone else ran into this. Hello to anyone from Google or the great beyond.
The Problem: Opening RBXL files in Windows Explorer starts Roblox Studio, but fails to actually open the RBXL file. (May also happen with RBXLX files, the XML counterpart to the binary RBXL files)