Here is how I read it using PHP:
Convert profile blob to useful data (Wiki).
A more up-to-date version of this can be found on Sourceforge:
profile &
functions. The same idea (substr()) can be used in pretty much any computer language.
Putting it back is basically the reverse, by putting all of the data back into one lump, then updating it into the database.
I haven't tried this yet, although I did create a PHP utility to directly view the contents of the blob (not on Sourceforge yet, but will eventually be located
here) with the intent of eventually being able to edit it directly from the same utility (like a hex editor), then moving to a more user friendly interface. My only concern about updating directly into the profile is that there is a Checksum field at the very beginning, and I'm not sure if it would cause any problems if you do modify it.
The hard work of breaking down what's where has been done, so all of the information you need should be there. From there, you'll just need to figure out the best way to inject the changes.