Mac OS X 10.6.8 & Pro Tools 8 LE

So recently my macbook pro decided it wasnt going to work any longer. I had been running PTLE 7.3 on it wonderfully for years. Without much money I decided to invest in a refurbished Mac and attempt to run my old software on it. However I did not notice that my old software was only for the Macbook Pro... So now I have a machine that is running Mac Os X 10.6.8 and that is not compatible with PTLE 7.3 Thus I bought a Pro Tools LE 8 disc from ebay, hoping to install and then download the upgrade to Pro Tools LE 8.0.5 for free as this was compatible on the chart. Well, upon receiving my disc for Pro Tools LE 8 and attempting to install I was met with several different error messages related to the installer failing. I was not even able to install the Pro Tools in order to install the update... Now I have spent over $350 on the refurb and Pro Tools 8 disc... I have a macbook running 10.5.8 but it has no firewire ports, I use the DIGI 002, and just to check I put the Pro Tools 8 disc in there and it booted up and was ready to install. So the disc seems to be good, but it is not being able to install on the 10.6.8 machine. Does anyone have a solution to this conundrum? I've searched and have yet to find one. Please Help!
sincerely,
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