I wrote the thing. It modifies the game code, not the save file. I won't say it's impossible that it won't brick your save, but you have to really, really REALLY try REALLY REALLY hard to do so. I mean like day one, crank up all the stats and/or money to max value to the point where it overflows physical memory limitations, kind of thing. But, for the most part, no it won't. In fact, that last time it caused something to crash on me was when I was testing out a feature I want to put (back, long story) into the injector and encountered a block of code in game that wasn't tested yet and caught a bug in the game.
Just remember, as the OP of the cheat injector said, the buying ability points can turn the achievement points negative, which is why there's a button to increase ability points.
