This is a hack to duplicate your credits. I used it to get over 200000000 credits in 10 minutes.
I hacked Robot Rage with Cheat Engine v5.2.
1.Go to Sell Parts and click on any part that you want to sell. (DO NOT PRESS "SELL NOW"
2.Click on Enable Speed Hack on the right in the window in cheat engine
3.Set the first bow to 0.00001.
4.Set the second box to 100000.
5.Click Set Speed.
Robot Rage will look frozen but it's not. Just keep clicking the Sell Now button as many times as you want. When ready un-check Enable Speed Hack and you will have loads of cash!