Redo Keynote template

I have a template in Keynote v6.6 (El Capitan) and I need it to be turned into a v6.5 template so I can use it on a non-El Capitan Mac. It is also quite large at around 110Mb so I also need some graphic optimising doing: SVG graphics need to be converted into PNGs and backgrounds need to be compressed for on-screen use (it's large because the images are print-ready. It should only take a couple of hours if you know what you're doing but you will probably need two Macs: one El Capitan and one not, so you can open the current one and build the new (older version) one. All template slides and content slides need to be built in exactly the same way; using the same fonts, colours, layers, etc. The file is here: [login to view URL]