What version of Adobe Acrobat [not reader] would I need so I could run it on a G4 1.25 ghz MDD running 10.4.11, that would also run on 10.5, in case I install that? I am going to look for some legitimate, used software, but want to buy the right version. Version 6 says it will requires 10.2.2. Would that run on 4, and maybe 5? Thank you.