Stealth Inc 2: A Game of Clones [NPUB31632]

Unimplemented function: cellHttp* cellSsl*
These are related to Network and i assume those are DRM or OL play.

sys_fs error: sys_fs_stat('/dev_bdvd/PS3_GAME/USRDIR/DLC/') failed: not found
Well I don't know really whether this game need DLC to start correctly or so..

sys_spu TODO: Unsupported SPU Thread options (0x2)
Eh..Well this thread options issue could be seen in other games. SPU behavior isn't open to public.
All those thans to RE by Neko. So merely do anyone in the team know about the SPU internals except him.

cellGcmSys error
rpcs3 has two WIP branch currently, master and rsx. most commits are done by Neko and Bigpet in master, and raven in rsx.
being a WIP as a playground, rsx codes haven't been ported or merged back into master now.
RSX behavior isn't open to public, you can find few docs about it. So similar situation as SPU.

So there should be many glitches / rendering issues, besides SPU not totally working well. PPU is already working now.

To help your emulation, you can either be a dev yourself and do some hard jobs, or find more games to test, with different Interpreter/Recompiler settings. Plus.. If you have PS3 and would like to help by setting up a testing environment you can contact those on IRC. Eh.. Or else just left the emulation for some time and check it again after.
You can always use git commit logs to view if anything significant was improved..

Probably the game not going further is caused by TrophInstall thread encountering an error. The same 0x28 write error can be seen in some other games, if I remember right.