Hi,
I think the KB you mentioned should be the one discussed in this blog:
http://blogs.technet.com/b/the_microsoft_excel_support_team_blog/archive/2014/12/13/forms-controls-stop-working-after-december-2014-updates-.aspx
Since MS14-082 Microsoft Office Security Updates for December 2014, some users have found that Form Controls (FM20.dll) are no longer working as expected. Please pay attention to the Additional Notes
in the blog:
If you are using a system with multiple versions of Office installed, all versions will need to be updated at the same time or other problems may exist.
- Example: Office 2010 Suite + Lync 2013 would require both the Security Update for Office 2010 and Office 2013 to be applied.
Make sure both versions has been updated and try the fix you mentioned, check the result again.
Regards,
Melon Chen
TechNet Community Support