Needing help with modding xml files...

[simsaddict777]

So basically I had tried two mods for making vampires to be able to bite everyone, however none of them worked (one had caused the interactions to totally disappear and then other had done something funky with the UI). I suspected they were not compatible and since I was not able to find another mod like that I tried doing it myself. However, the game runs just like before when I tried it. I looked at to what they did and tried do the same thing however it still appeared with no changes. Basically, under Electronic Arts -> The Sims 3 -> Game -> Bin -> Gameplay -> GameplayDATA which I opened up I went down to SocialData Ep3, which is what I read that this person did http://www.modthesims.info/download.php?t=424724, and then I copied an xml for that from another persons mod and replaced it with the xml I had. That was after I tried doing it manually and both came out with the same results, nothing happens.
I suppose it is better then breaking my game.

[lorenrose1013]

Well if the mod for vamps to drink from everyone is there in that link, and updated for pets, why do you need to make your own (no offense, just asking) Unless you need a different version? And when you were in the GameplayData, did you export the file, or edit it right there?

[simsaddict777]

I tried that mod however the bite interaction disappeared. I don't remember if I exported it or not, I thought I did but I could try again.

[CmarNYC]

You should never modify the game packages - did you make a new package with the modification?

The xml can be changed in game patches. I see in the mod you linked there's several versions - did you try using the one for your game's patch level?