We do save our templates down as far as possible to allow you to submit. Template packages will always include AI and EPS files, saved down to legacy formats that should open properly in CS3 or higher. We also provide INDD and IDML files for InDesign users. You will only be able to open the INDD templates in CS6. If you are on InDesign CS4 or CS5, please refer to the IDML files. IDML (InDesign Markup Language) is an XML-based format, introduced in Adobe InDesign CS4, for representing InDesign content.
If you aren't able to open our templates, please email us at email@example.com and we will do our best to help!