Same problem. I've got a 1.5 with K:5101 D:4920 and a rented 007:AUF that does NOT say platinum on it, rented from BlockBuster.
Here's what happens. If the xbox is clean (restored from backup image) then 007 loads up with no problem.
If I load the gamesave onto the xbox then boot 007 it will not load and brings up a screen saying "xbox needs service, call # in manual".
I am using Mordens modified audio hack which I assume is already signed as there are no signing instructions included with the package from xbins.
I'm using xlinux / swap to get the gamesave on the HD so memcard issues are not a problem.
The only thing I can think of is either this version of 007 is fixed, even though it doesn't say platinum on it. Or something is different about my xbox or my combination of kernel and dash. My xbox came loaded with 4920 but was upgraded by live to 5xxx (live 2.0) then downgraded using 4920 from slayers (downloaded from #slayers). My unit is also a SW/Tetris Bundle.. which I hear may make a difference.
Any info is appreciated.