Good day Ben,
This is the forum for SendNow, a service for file sharing that's part of the Acrobat.com family. I would suggest you post your question over in the InDesign General forum.
Acrobat Community Manager
I believe InDesign 4.0 would be InDesign CS2. That shipped in May 2005.
I think that would be too old to run under Lion. InDesign CS2, I believe, was designed to run on PowerPC processors. You could use Rosetta under Snow Leopard (10.6) to run it, but Rosetta was killed with Lion (10.7).