BIOS

[LunaMoo]

No, PPSSPP by design will never emulate psp OS(and it is full size firmware based on linux, not just some "BIOS").

For looks you can use RetroArch which does include(althrough currently outdated) PPSSPP core and for whatever reason has an ui based on Sony's XMB.

You can also forget about accessing any official servers from PPSSPP, things like that just brings up legal trouble to emulation projects and nobody will risk whole project just to unlock some stuff in few games. FYI through ~ things "requiring" psp web browser can also be downloaded using any other browser on any other platform, just google for link, downloading was never a problem which actually lies in encryption.

Updates are encrypted with keys that emulators does not have access to and most dlc's either require separate update or come as game update and while usually it's enough to decrypt all of the stuff using real psp and then just move the files to emulator, in particular case of KillZone something else is also causing problems and AFAIK will not work on PSV either ~ you can only play that dlc content on real psp.

That will continue until some fan of this game who cares enough figures out what's wrong and hacks it, but even then if it is encrypted with one of those unobtainable keys, it would still require real psp to decrypt it just like pretty much all updates and few other dlc's. PSP firmware being emulated or not would NOT change anything about it.