From Nikonians Wiki - FAQs, Photo Glossary, Good Photo Locations, Help
Why do you only have a Windows version of Annotate available?
Answer: A lot of photographers are using Macintosh and we are more than aware of that. Our current goal was to create a first version of the software quickly and thanks to the Nikonians members, where more than 80 percent are Windows users, we have been able to fine-tune features based on community requests. We are listening to feedback from all Nikonians and almost all of the requests from the community have been implemented. There has been a few inquiries about a Mac version and we have decided that we will release a version that will run on Mac OS X in 2010.
For now, you have an option to use virtualization software and run Annotate on Mac.
Is not raw formats, e.g. NEF supported?
Answer: Yes, Annotate Expert (V1.20 and later) supports multiple raw formats, including NEF. For list of supported formats, see the pdf Users guide bundled together with Annotate, available from the Help tab.
In order to open NEFs, you will need a WIC compliant codec that supports NEF format. You can use the free Nikon Raw codec that supports NEFs: http://www.nikonimglib.com/nefcodec/ or the FastPictureViewer codec pack: http://www.fastpictureviewer.com/codecs/
IF you are having problems opening any RAW files in Annotate, please make sure that you have WIC (Windows Imaging Component) installed. WIC is present in WinXP SP3, Windows Vista and Windows 7 by default. In case you can not open RAWs in Annotate, you probably need to download and install WIC separately from Microsoft: http://www.microsoft.com/downloads/details.aspx?FamilyID=8e011506-6307-445b-b950-215def45ddd8&displaylang=en
I cannot open .DNG files If you cannot open .DNG files, you need to install a codec that can open them. You can for example use the FastPictureViewer codec pack which supports many formats: http://www.fastpictureviewer.com/codecs/