You can learn how to convert InDesign CC-CC 2017 to CS5-CS6 without IDML, using MarkzTools for InDesign plugins by Markzware.
You can batch convert InDesign to IDML without Adobe InDesign layout application installed, via the MarkzTools2 app by Markzware. See
You can convert InDesign CC 2015 files to InDesign CS5, CS5.5 or CS6, via MarkzTools for InDesign plugins by Markzware.
ID Util for macOS, a Mac app, shows the Adobe InDesign version of INDD CS2-CC 2015 files for Creative Suite
Convert InDesign CC version files to InDesign CS5, via MarkzTools2 Bundle. See file conversion video about Markzware InDesign plugins.
Get InDesign CC 2017 files incoming, but have CS5 or CS6 as your version? Use InDesign plugins in Markzware's MarkzTools2
A MarkzTools InDesign plugin can convert InDesign CC to InDesign CS6. Use a plugin in the MarkzTools2 Bundle, to open
MarkzTools file conversion software can convert InDesign CC to InDesign CS6. See Markzware video on opening InDesign in an earlier
Markzware's InDesign plugin, MarkzTools, can convert InDesign CC to InDesign CS5. See video on how to open newer version in
Markzware's MarkzTools2 Bundle can open InDesign CC-CC 2017 files in InDesign CS5-CS6. Video shows how to access INDD Creative Cloud
You can open higher version InDesign CC files in a lower InDesign version (CS5-6), via plugins in Markzware's MarkzTools2 Bundle.
Markzware shows how to open InDesign CC 2017 in Adobe InDesign CS5 via MarkzTools for InDesign CS5 plugin in MarkzTools2
You can use the MarkzTools2 Bundle to open InDesign Creative Cloud in InDesign CS5-CS6. With this article & video, Markzware
Markzware shows how to convert InDesign CC 2017 to IDML, so CS5 & CS6 users can view the content. Watch
Open higher InDesign versions in lower Adobe CS applications. Open higher INDD version files in lower INDD versions via Markzware