Originally Posted by delphidb96
On the other hand, there is a nifty program called BookDesigner which can take a .lit file (NOT one that has been laden with DRM) and, through the magic of good programming, directly import the files contained in the .lit right into the main BookDesigner editor. If there's no editing to be done - and there's *ALWAYS* editing to be done! - you can then just save to mobi format. Mobipocket Creator requires you to do the stripping from .lit to .html (using ConvertLit) on your own, whereas, as long as you have ConvertLit installed on your system, BookDesigner will handle it all for you.
Please DON'T use Book Designer to create Mobi books! I agree, it's a great way to create books (it's what I use for all mine), but it creates Mobi books in a very old format, lacking many features, and with no metadata.
Best thing to do is to edit your book is BD, export it as HTML from BD, and then use Mobi Creator (or Tommy's "html2mobi" PERL tool) to create your Mobi book. I've written a tutorial here
which illustrates exactly how to do it.