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Yes this was the issue.
You seem to have an incorrectly narrow definition of DRM. From wiki "DRM technologies try to control the *use*, modification, and distribution of copyrighted works" [emphasis mine] Preventing a program from launching because the license no longer matches the underlying machine is an example of DRM.
Yes I did pay, and no it does not ask for a license key. It seems if you bought it from the App store it insists that you sign back into the app store before it will launch which of course you cannot do when having networking issues.
My original statement stands. DRM only screws those who pay.