In CHDK trunk 6298-6306, I updated the hostlua scripts:
It now uses an adapted version of the chdkptp param parsing code I mentioned in the previous post. This doesn't exactly match every quirk to of the CHDK C code, but it should be much closer, and does handle ultimate.lua correctly.
I also added functions to camera_funcs.lua which were added to CHDK after the most recent release of hostluaPortable, and fixed some that were broken. Support for rawop is included, but some functions (the raw value / ev conversions, and histogram range) require a recent build of CHDK hostlua since they use fmath
A zip with current scripts and hostlua compiled from the current trunk is available from:
https://app.box.com/s/8yrlmlvap5v55bwx2j3tv611h43indxv
To use the updated functionality with hostluaPortable, you can just unzip the files to the bin directory, overwriting existing files.