On Calibre 0.9.16, New Features added as below:
- News download: Do not convert all downloaded images to JPG format. This fixes the problem of PNG images with transparent backgrounds being rendered with black backgrounds
- CHM Input: Support hierarchical table of contents. Do not generate an inline table of contents when a metadata table of contents is present. Also correctly decode the text in the table of contents
- Get Books: Add the beam-ebooks.de store
- Make custom yes/no columns using icons put text values under the icons.
- Driver for LG E400 and SayCoolA710
- Speed up device connection when there are lots of books on the device by not generating cover thumbnails unless they are actually needed.
- Have the metadata download dialog remember its last used size.
And also some bug fixes.
I am using 64bit Calibre program. It is not limited to using only 3GB memory when converting large documents.