Lunge track is one by Sash!, who has released only 3 tracks in since 2002, 2007 - Ecuador Reloaded, 2008 - Raindrops, 2009 - Stay 2009.I don't think that track is older one.
Last one is imo too new, so there are only 2 possibilities. I would choose first one (Ecuador Reloaded). Fits better in Lunges and it is second remake in this release, next to chest track Infinity 2008. We'll see if I'm right. 
Warmup song is still a big ?.
BodyPump & Body Balance - Best Combination!
Check my unofficial tracklist site:
http://lesmills-tracklists.uuuq.com