As I said in my previous post, for PDFtoMusic to work, your PDF needs to contain data on individual "elements" of the page - something it can recognise as a discrete vertical line with a "dot" at the bottom of it, long horizontal lines corresponding to a staff etc. It will not recognise a "photographic" image of a sheet of music.
Printing directly from a Noteworthy Score via a "PDF Virtual Printer" (I am currently using one called PDFCreator, but there are several free ones out there) may produce a file that PDFtoMusic can process. Converting to an image file, importing into Open Office and then converting to PDF may lose the information which PDFtoMusic needs. The "metafile" may keep the information there for the PDF, but if it behaves like bitmap art, it may be lost. The only way to find out would be to try it and see what happens.
I don't have Noteworthy, will try output from MuseScore (free score setting programme) via it's direct PDF export and compare with results by printing via PDFCreator. I wil report back.
Quack!
GtD.