CHM to MOBI conversion (WinXP) 0.8.22

[newbi]

I perform an ADD BOOK on the chm file and, whilst I can't seem to find a log, running calibre-debug -g in the command prompt provides the following output:

Worker Launch took: 0.452999830246
Job: 1 Read metadata (0 of 1) finished
Read metadata (0 of 1)
Traceback (most recent call last):
File "site-packages\calibre\customize\ui.py", line 312, in get_file_type_metadata
File "site-packages\calibre\customize\builtins.py", line 168, in get_metadata
File "site-packages\calibre\ebooks\chm\metadata.py", line 164, in get_metadata
TypeError: __init__() takes exactly 4 arguments (3 given)

Then I convert from CHM to MOBI

Job: 2 Convert book 1 of 1 (swfStudio 3.8) finished

When I view the book, it's all indexes and no detail. How to proceed?