I can confirm Coded Arms working with Hookboot 0.91 on my Jap 1.0 PSP. You must have a clean UMD rip of the game.
As per the .INI file, you need to create an empty text file called CODED.ARM in a directory:
\PSP\SAVEDATA\ULAS42009000
You also need to overwrite the \PSP_GAME\USRDIR\MODULES\*.PRX files with the same files from an earlier game that boots on a 1.0 PSP. I used the ones from Untold Legends, the files from Twisted Metal should also work.
Works fine but won't save for some reason.
This is as well as the other games I can confirm working:
Untold Legends
Lumines
NBA 2K5
Puzzle Bobble
Wipeout Pure
Mercury
Not working:
THUG2 (1.2Gb, don't have a MS that big

Hotshots Golf
This is just using the "GENERIC" hookboot.ini file and the "makepbp.bat" for each game.
This thread has a good compatibility list:
http://forums.maxconsole.net/showthread.php?t=7307Download the new 0.91 from:
http://www.maxconsole.net/?mode=gotodownload&downloadid=731