I think it would make more sense for the engine to be toggled instead of press and hold down to turn off. Or the engine could have a toggle and a hold down some button to turn on.
There's a bug related to pressing down with Pheus standing on Mor. If Pheus is standing on Mor, at the end of Mor's headbutt animation, Mor will jump (not high enough for the ending). If you press down and Mor's bash animation finishes as Pheus is falling in front of Mor, instead of being knocked back, Pheus is sent flying upwards and moved back the same amount. Otherwise really fun and beautiful game.
I find that the fastest wins are with the pistol upgrades, then the shelter and the health station, then the uzi and ups, then the ar and ups. Up the health station once as well. Sleep and heal when necessary. Otherwise, keep repairing that balloon.
I think the cure zombiism path is somewhat bugged. I've beaten the game every other way, but I can't seem to let the doctor either die or leave lab. It's been 153 days.
LOL! Once you max everything out, the game becomes ridiculously easy. Lessee Story done in 10 days and Classic in 9. In both cases, I was accused of cheating (haha).
 "Pheus and Mor"){kind=icon}
 "a Grain of Truth"){kind=icon}
 "Into Space 2"){kind=icon}
 "40xEscape"){kind=icon}
 "Balloon in a Wasteland"){kind=icon}
 "Rebuild 2"){kind=icon}
 "Walkinator"){kind=icon}
 "Villainous"){kind=icon}
 "Blocks With Letters On"){kind=icon}
 "Learn to Fly 2"){kind=icon}
 "Red Remover Player Pack"){kind=icon}
 "The I of It"){kind=icon}
 "William and Sly"){kind=icon}
 "Space is Key"){kind=icon}
Yes, thatnx for that info! : )