[At_Libitum]

Some issues I encountered:

When you download a book in Marvin and then later import it into Calibre (where it does not yet exist), it does not update the Collections, Word count and Series columns in Calibre. It does however retrieve the Marvin subjects to the Tags column, too bad the plugin takes this info from the book and not from the (changed) metadata in Marvin (I had removed all tags and added my own, after adding the book to Calibre, the Tags field contained those that came with the book, not the ones I added in Marvin).

When I then open the Marvin window (from the plugin button) and want to update the info that way using the button at the bottom of the dialog I get the following

calibre, version 1.3.0
ERROR: Unhandled exception: <b>TypeError</b>:'NoneType' object does not support item assignment

calibre 1.3 isfrozen: True is64bit: False
Windows-7-6.1.7600 Windows ('32bit', 'WindowsPE')
('Windows', '7', '6.1.7600')
Python 2.7.5
Windows: ('7', '6.1.7600', '', 'Multiprocessor Free')
Traceback (most recent call last):
File "calibre_plugins.marvin_manager.book_status", line 981, in dispatch_button_click
File "calibre_plugins.marvin_manager.book_status", line 1373, in refresh_custom_columns
File "calibre_plugins.marvin_manager.book_status", line 2072, in _apply_date_read
TypeError: 'NoneType' object does not support item assignment

The last line seems to indicate it cannot find something, yet all of the available fields have been mapped in the configuration dialog of the plugin

Also, when I get rid of the dialog showing this error, I am left with this (see screenshot) that won't go away unless task killing Calibre

However, doing the same from the context menu that opens the side-by-side metadata dialog, then updating works.