If a theme has a custom keyguard set, but it is not showing, set your Sidekick Slide's keyguard to the default one through Settings->Key Guard & Security. Then reboot your device by pressing 1+@+0 (the 1 key, the 0 key, and the @ symbol by the spacebar at the same time)
You fake it! You can use the screen shot simulator Photoshop files that silversidekick and fatb0yslim33 put together to make a "screenshot" that looks like it was taken on the device. You can download these files from the Theme Simulator page. Thanks guys!