'adobe application manager required to verify your license is missing or damaged' (Lightroom 6.0 standalone purchase)

I purchased Lightroom as a standalone download for PC from Amazon as I didn't want to get locked into any of the Creative Cloud business.
esp. since I have other already paid for Adobe products on my PC.
So am opening Lightroom and on start up I'm getting the 'Adobe Application Manager, required to verify your license is missing or damaged' please download from adobe.com/go/application manager etc box.

The programme then seems to proceed anyway and seems to work ok without it.

So do I need to download? (I would rather not if it will affect my other Adobe software or keep throwing this CC stuff at me).

And if not is there a way to stop the annoying box appearing on start up if I don't need it?

Thanks