I have an Indesign CS3 file that I need in Indesign CS format. To get a file from CS3 to CS, you need to save it from CS3 as a CS3 INX, open that in CS 2, save it as a CS2 INX, open that in CS, then save that as a CS file.
Attached is a test file. The real file is several hundred pages long. If you have CS, CS2, and CS3 and can turn this test file into an Indesign CS file, you should be able to do this job. Don't worry about missing fonts, graphics, and effects that are not compatible with Indesign CS. I just need to be able to open the file in CS and will correct those things later.