On Windows7/64 bit: C:\program data/application data\stardock\iconpackager does not exist. There is no application data folder inside program data.
C:\ProgramData\Stardock\IconPackager does exist and contains one file, sig.bin
The path: C:\Users\username\AppData\Local\Stardock\IconPackager also exists and contains 3 files:backup folders.ini, backup.ini, and file icons.ini
All installed themes are found in: C:\Users\Public\Documents\Stardock\IconPackager
I click on the iconpackager file, iconpackager opens and the package is there but there is no preview and I cannot apply it.
I've been getting that also. Not only that, but when you close IP and relaunch it, the package is no longer in the list as installed.
I just open IP, click on Add Icon Package/Install from disk, then browse to the IP and install it. It seems to "stick" that way.