I frequently create large images to show a lot of detail. In Scrivener, I edit the image and set the pixel size smaller so that it fits the page. When the target is an ebook, the image can be opened into a full page to take advantage of the detail.
The problem occurs when I output to Word 2010. The size limits that I set in Scrivener are lost and the file is much larger than the page. The semi-workaround is to export in html and open with word–not elegant, but it mostly works because the image sizes are what were set in Scrivener.
Thanks for the report. Hopefully this won’t be too difficult to fix; it seems the size set is just getting lost on the RTF/DOC/DOCX export, as other formats work correctly, so it may just be a small tweak in the code. It is possible to resize the images once you’ve brought the document into Word, but if you have a lot of them that might take a while–I’m not enough of a Word 2010 guru to know if there’s a quick way to resize all the images in the document at once by percentage or such (or if that would even really help you much, since you may need to adjust each individually in any case for optimization).