I forgot to mention it is for CS5, compiled using the AECS5 SDK for 64-bit intel, Mac OSx 10.5.
The user's specs are...
Model Name: iMac
Model Identifier: iMac6,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.16 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 4 MB
Memory: 3 GB
Bus Speed: 667 MHz
Boot ROM Version: IM61.0093.B07
This error has to do with the code that calls PF_Cmd_SEQUENCE_SETUP. Is your effect returning normally from that command on the user's system?
I normally return PF_Err_None, but if PF_NEW_HANDLE or PF_LOCK_HANDLE fail, I return PF_Err_INTERNAL_STRUCT_DAMAGED.
Is 25::3 from PF_Err_INTERNAL_STRUCT_DAMAGED?