Cannot Place Crack in Base Game after installing Sims 3 Pets

I downloaded and installed the G4TW Sims 3 Pets and I followed the instructions that came with the rar file, but I have a purchased versions of the base game on a disc so when I try to put the crack in the base game a pop up comes up saying its not a writable disc and ejects my base game from my drive.  I tried playing without the crack but then I get a pop up saying to place the sims 3 disc in the drive.  I don't know what to do! HELP

Hello,

You're trying to copy the crack to the wrong location. Please watch this video to make sure it's in the right place.

Note that you no longer have to use your disk after placing the crack.
Please let us know if you run into problems.

I tried placing the ultimate crack to fix my sims 3 pets having no towns or availiable menu options, and now when I run as administrator, a pop up comes up saying it is not working.  I am getting so frustrated.