Today I encountered a strange anomaly in SharePoint Designer 2013.
I pushed a fresh Windows 8.1 image and installed Visual studio 2013 Premium Update 2 (couldnt go for update 4 due to informix driver). I installed sharePoint Designer 2013 and wanted to use it to resume on a workflow. When I loaded it, to my dismay SharePoint Designer displayed an empty workflow ready to start designing … I thought I lost my work. I started looking for a solution and I encountered this post http://community.office365.com/en-us/f/154/t/264867.aspx
To cut story short they ask the user to install this SharePoint Designer update http://www.microsoft.com/en-us/download/details.aspx?id=41467
I did so and it worked. So why things worked before the refresh of the image? My conclusion is because before i had Visual studio 2013 Premium Update 4, So I think something required by SharePoint Designer 2013 is missing in Update 2 but available in Update 4