The best place to ask questions is the developers' collaborative space on IRC, particularly at on the #virgil3d channel. Remember that developers are in various time zones, so be patient after posting your question.

A: Yes, if you download it from the official GitHub source. Avoid untrusted sites promising "modded" versions.

Start the VirGL server background process within the overlay application before launching your game launcher. Performance Optimization Tips

: For rendering directly in an X11 window rather than as an overlay, you can use the environment variable VTEST_WIN=1 in your emulator shortcut. Releases · alexvorxx/VirGL-Overlay-Rebuild - GitHub