GenP4.0.4 Photoshop Blank home screen

After applying the GenP v4.0.4 patch to Photoshop, it's home screen is just blank/grey. I’ve followed the guide to the letter and double-checked all permissions, but nothing works. I’ve even tried a clean wipe and reinstall, but no luck. Photoshop itself works fine—I can create new files through the top menu bar—but the home screen remains completely grey.