Finding the right Adress

Hey, now that i finally have some more time to work on my c++ trainer i figured trying to find out how i can modify an value.

I have the c++ code to do it (i think), and i know that this might not be in the correct forum but for some reason i do think it is. (Because i have questions to how to use a certain address.)

Right, so i found the address for money in Assassin's Creed 2, i can modify it and everything, now i know that the address changes when the game restarts etc. now i need to find out what really is the proper address.

When i do 'find out what writes to this address' (in cheat engine) then i find a code which when i modify the value the game crashes.

So i read this tutorial here and it made me think if i could use this address then instead:

I found these:

- AssassinsCreedIIGame.exe+ED818F | Code: mov[ecx+10],eax (works to NOP)
- AssassinsCreedIIGame.exe+F1E8D3 | Code: mov[edi+34],esi (dunno)

So like i said i read the tutorial so i know that the exe+adress points to the proper address.

I wondering can i use this code in some way to modify the value rather then using the exact adress? And i'm pretty sure i saw that 'code' thing in c++ before too eax and mov.

Can i use the code type to modify the address?

And last but not least, if none of the above? How do i really find the address that i need? I keep finding the same address so i figure this is the one, but every time i edit the value to have like 99999 it crashes (using my c++ trainer) whenever the money changes (i throw money on the ground).