CopyFlow Gold for CS6 supports InDesign CS6 through InDesign CC2014.
The current versions of CopyFlow Gold for InDesign CS6 also works with the current CC 2015 version of InDesign - but we have been warned by Adobe that there are changes coming which will require a major upgrade for CFG. When that happens we we will be charging for this upgrade.
Adobe discontinued Extension Manager for CC 2015 - so you must download ZXP Installer to install Copyflow Gold into InDesign CC2015 - unless you had CopyFlow Gold already installed in a copy of InDesign CC2014 which you upgraded to CC2015 - in which case it may simply apprear.
Otherwise, to install CFG with CC 2015:
Download the latest demo version of CFG for InDesign CS6 from www.napsys.com. - a. zxp file.
Then download (right click link - to Download As... ) the installer for
Macintosh: http://www.napsys.com/ware/ZXPInstaller.dmg
or download (right click link - Download As... ) the installer for
Open the ZXP zip or dmg & install 'ZXPInstaller'
Launch ZXP Installer and use it to install the new CFG .zxp file you downloaded above into InDesign CC 2015.
Restart InDesign. CopyFlow Gold should appear under: Windows->Extensions->CopyFlow Gold.
If you are a customer and have authorization keys - enter them now. If you are using the demo - enjoy the trial.
For much more info on CopyFlow Gold: http://www.napsys.com/products/copyflow-gold-for-indesign-cs6/