Customized labels not working

Line 294 of switchtheme.module should read:
$options[$name] = variable_get('switchtheme_' . $name, $label);
($label has been changed to $name)
Note that if you make this change the theme selector form will show blank options unless you specify the label in the admin menu (it doesn't default to the theme name).

On my end the switch theme form works fine. Changing the labels in the admin settings changes the select boxes in the switchtheme block. I'm using the master version and not the 1.0 version. Perhaps it was fixed and a 1.1 version will be on the way soon.

What radio buttons labels?

This happens in 7.x (I had v 1.6 2011/01/07 23:41:22) and has been fixed in the dev version. Either upgrade to a dev version, or if you feel unsure, manually update switchtheme_options() in your switchtheme.module file:

old:
$options[$name] = variable_get('switchtheme_' . $label, $label);
new:
$options[$name] = variable_get('switchtheme_' . $name, $label);

Edit: Nevermind guess I should read the comments on necro threads instead of scanning them ...