bonapart, new GUI looks promising, but there are three problems with it:
You can't choose default roms location. In emu main screen I can choose only bios scph1001.bin So can't play games. Maybe I missed something?
When you choose frameskip or cycle multiplier it's nearly impossible to scroll to bigger numbers like 6. You have to use arrow keys.
Sometimes I can get to menu. I tap 'PSX4M-Gui' and nothing happens. I have to 'ctrl+backspace' and go back to the emu to fix it.

GUI needs a bit more polishing and it will be great!