Ensure and OpenIV.ASI are both installed (they should be green).
Windows copy-paste is simple and doesn't have OpenIV's conflict-checking overhead. It takes 10 seconds, not 10 minutes.
# Process OIV metadata print("Processing installation instructions...") self._process_oiv_metadata(install_dir)
or high-res texture packs) often modify gigabytes of data. The installer isn't just "pasting" files; it is opening, modifying, and rebuilding heavy Disk Bottleneck