this post may seem like a duplicate from my other post, "Is is possible to export Inkscape files for inDesign?" but this completely different.
I need to open my inDesign CS5 files in Ubuntu but I can't seem to find a free vector program that can open inDesign files ( or files exported by inDesing CS5 )
Please note that I can't work with a bitmap or a layer merged vector.
The development version of Scribus can open IDML files (InDesign Markup Language, the official import/export file format for applications that have to work together with InDesign). I am not sure how good the IDML support is currently, so you will have to test yourself...
If you want to try the latest development version of Scribus, there is a PPA for that. But remember that these are daily builds of the development version, and they are probably not ready to be used for production work yet (and every day a new version will be available, which may fix some issues, but also introduce new ones).
I think you can export a PDF file in inDesign and then import it in Inkscape.
FYI: IDML files: Indesign Markup Language files are publicly specified format designed for interchanging data. INDD (indesign documents) are NOT openly specified, but MAY contain useful bits of information following the same conversion described here.
If you can get your hands on an "IDML" export file, any "zip" package utility can unzip it, revealing the images within. This can most easily be done by renaming or appending .zip to the file name. This also reveals the document's native xml-like code and structure, which contains somewhere the raw text, albeitn marked with html like tags. Be forewarned, this is almost certainly a one-way trip... making changes and rezipping the file will almost certainly be rejected by adobe programs.