Well actually it's Mobipocket Creator that is the problem, since Mobipocket got Borged by Amazon the software hasn't been updated, since about 2005 that is.
Creator is heavily dependent on some MS proprietry 'features' in older versions of IE, which even MS no longer support.
The only solution that I have found is to downgrade to IE7 or 8, which I wouldn't reccommend for security reasons.
The only ways I have found to create Kindle content since the demise of creator are Amazon's Kindlegen (a distinctly unfriendly command-line tool. See: -
http://www.amazon.com/gp/feature.htm...cId=1000234621) or Calibre
http://calibre-ebook.com/.
Unfortunately neither option gives anything like the degree of control that Creator used to and neither will accept word .docs as input.
I have found that the best results are obtained by creating an epub and then converting that in Calibre.