Inverting input disables play, exit and report bug buttons.

After loading the designer with the craft (Bug reproducer Mk2) you use the finger tool to hover over the front wheel, without moving the camera, and change both friction sliders. Then you move the camera to do the same for the back right wheel. Next you scroll dovn and change the toggle that inverts the motor controller, without using the hidden propertys button. You might have to try this sequence several times (the pictures have the finger tool pointing out the relevant parts). After that the ‘play’, the ‘exit’ and the ‘report a bug’ buttons only play their sound and change color like normal, but nothing else happens. This bug doesn’t seem to happen, when the second FPS display is active.
Edit: after trying to upload the craft I got an error message that read: ‘An unexpected failure occurred: Object reference not set to an instance of an object’, and the colors of the craft changed as seen in the uploaded pictures of the craft. After removing the wheels from the craft, there was no issue uploading it. Undoing the removal of the wheels with the undo button enabled me to upload the craft with the wheels.