Solution by ali0gamer on 2021-08-18 07:28:
Main function is at base + 0x1030. Program gets Activation serial and then asks for the hash value calculated by the algorithm.

Solution by InsideExploit on 2021-08-25 23:22:

Solution by tomxmm0 on 2021-08-30 10:51:
Instead of trying to figure out what the numeric activation key calculation process does, we can copy the same process into our python code and use it to calculate the numeric activation key for our own serials which we create.

Solution by X3eRo0 on 2021-09-02 17:38:
The process of creating the keygen is very easy once you understand the way it is generating the key from the input serial. It is easy because it is doing some operations on the input serial to generate and then later that input is checked against another numerical input that is your key for the particular serial you entered. I just implemented the same generation algorithm in a python script and printed the final number that we get. That is our key.

Solution by g3chantr on 2022-01-15 20:05:
This solution contains a code analyse and a python script to generate a activation key depending of the serial key. It's a nice chall !Thanks