Hi, i have checked your attached quark file (contain 15 pages), i have Quark V4.1, V6.5 & V9, But Actually as i know that to convert to Indesign or Illustrator CS5, it should be rebuild inside these programs, and i can do that professionally.
about opening your file via Quark 5 and save as Quark 4 to open in Indesign, for sorrow i haven't V5 to save as 4.
ready to discuss.
pm me for more details and to give you a sample if you want, I am interest.
Thanks, George.