Fix the last GUI bugs

[ChrisViral]

The UI still acts very strange. I can't tell if it's by being related to the HydroJeb part, from the strapped-on RenderingManager replacement I snuck in, the on screen button, or my unfamilliarness with the code, but there are still some oddities.

Have to fix the following:

• [x] The panels in the editor only show the second time it is entered
• [x] The on screen button only shows after pausing the game
• [x] Errors are thrown when pausing the game
• [x] The on screen button stays in the space center and in all subsequent scenes
• [x] LineRenderer errors after going to the pad from the second entry in the VAB

[ChrisViral]

Most of those bugs were fixed by switching to the AppLauncher system in #4, but there are still a few bugs to verify before closing this.

[ChrisViral]

Looks all done here, closing.