I dont know what you mean with signing date, but the file was created on april the 26st in 2012, like the wfx64.exe (I use a 64bit win 7). But I already did have the software installed some weeks before, so shouldn't they be a bit older then?
The last time they were in use was today of course.
I recently reinstalled my whole os and started dircetly with beta 2.
Edit: I also made a restart, which did not help. The rc was installed over the beta 2 with Stardock Central.