I'm no expert on this, but getWarpButton shouldn't just fail normally.
The App function in question does the usual exe call and returns that retrieved value (after casting it to button, if a value was found). So that end really should work, any errors might occur at the place this function is called (no check for null), probably because the space systems are not set up properly.
Have you tinkered with the RHCD episode in question? Are the space systems all properly set up?
And what exactly do you mean with revised source code? Is Systems\Utils affected by that?
Posting the stack trace could help, as without there is really only guessing what exactly might have gone wrong.