Если я правильно понял то по сути
AX 7 это AX 2012 R3 с интерфейсом HTML5.
http://diginomica.com/2015/03/19/mic.../#.VagwrhNViko
Цитата:
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We’re going to keep the data model and the business logic the same between AX 2012 R3 and AX 7 to keep the upgrade simple.
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Yes there are cosmetic changes but you also get a move to an HTML 5 based user experience.