Convert DOC to AWW

You shouldn't have any issues attempting to convert standard Microsoft Word Documents directly to Ability Write Documents (.doc to .aww conversion). It appears, however, that your options are limited to using the original software.

Using Ability Write itself, you will be able to easily import DOC documents and re-save them in the proprietary AWW document format. 

Alternatively, you might be able to find some online converters capable of such conversion, but using Ability Write is certainly your best bet.