Oh yeah I haven't done much testing on PSP Go external memory (since I only have a 128MB one lol so I could only test like one homebrew and one PSX game). I will try to look into it but for now I recommend you always use the internal memory.So I installed the exact way it was explained. Everything runs as intended, the issue was when I chose the launcher always setting to replace xmb. Once I disabled it, it went back working. The only thing that didn't work with launcher replacing xmb setting was psp games, got the blue screen after loading one. Probably a path issue, I was running games from the psp go ms0, not ef0 internal. That was the only issue I found. Latest version as well.
Oh and also, if you use external memory make sure you also have the ARK savedata folder in it, otherwise ARK might not find the installed files (though ARK should work without the savedata folder).
Sure, I'll look into it. Probably an issue with how the plugins are loaded (it changed a bit to accomodate the PS Vita with per-game plugins).I noticed that the latest release breaks when loading the Custom Firmware Extender plugin (Github link). Could you take a look into it?