Purchase the Adele version at Karaoke-Version.com
KV Adele version is in A at 136bpm
David Nail version is in D at 120bpm
In Audacity - open KV Adele version
Select the full track
Effect - Change Pitch - In HalfTones Box Type in -7.00
Makes sure Use high Quality check box is checked
Process the pitch change
Effect - Change Tempo - In Beats Per minute from - enter 136, to - enter 120
Makes sure Use high Quality check box is checked
Process the Tempo change
Sing along to the modified track with a lyric sheet to see if it works for the way David sings it.
If it works for you - Purchase a karaoke cdg creator program and create your cdg file to match the music.
I posted the first 1:45 of the modified track at
http://dsm2000.net/Download/NAIL,%20DAVID%20-%20SOMEONE%20LIKE%20YOU%20TEST.mp3