There's a new version of the Gameboy emulator and debugger BGB. It is a recommended upgrade for all users.
New features in BGB 1.5
http://bgb.bircd.org/
New features in BGB 1.5
- AVI writer
- Greatly improved efficiency (about 10-30% faster, depending on the system)
- Improved accuracy
- Improved sound quality
- Lower audio latency
- Preview screenshots in select state window
- Improvements to debugger, including selectable RGBDS or WLA assembler syntax, "ld d,d" debug messages, and editing the palette in the vram viewer.
- Fixed a large number of bugs, including "alt+F4 loads state", and "timing in LSDJ is unstable"
http://bgb.bircd.org/