There are two ways to upgrade your software:
The first is to take someone else's software. They worked so hard to get it, why wouldn't you take a copy? Just make sure to erase the logs so he can't trace your IP back. It's as simple as that.
The second way is to upgrade it yourself! To do that, you only need to purchase a license for your software and then do research on it. It doesn't matter if you take the software of someone else or not, you should always be able to do research on it in the university to upgrade its level.
So you could go find that v6.1 cracker and copy it then do research on it. You will upgrade it each time you do a research on it.