Always have the game closed when you SAVE the file!
You can edit files with normal NotePad but I recommend installing NotePad++[notepad-plus-plus.org]

Go to C:\Users\name\AppData\LocalLow\AMG






name = your PC user name

There you'll find BMS/SMS directory. They use the same SaveFile so you just need to edit one.

Edit SaveGameMain.es3 with NotePad++[notepad-plus-plus.org]

Travel to line 292 where you'll find all "passiveUpgrades" (Powerups)


























Edit "upgradeLevel" value as you wish.
























SAVE and start the game.