How to disable sparkle.framework updates for specific app?
You can try steps listed below - it worked in case of All2MP3 app, that was taken by rogue developer and changed into malware deployment platform.


Make backup of your original old app version!
Right click on the app and choose Show Package Contents.
Open info.plist file in your preferred text editor (I use TextWrangler)
Search for SUEnableAutomaticCheck
In the line below change YES to NO
Save file. Your app should stop updating automatically.