Should it be possible to build an add-in using ArcObjects SDK for .NET 10.2 and deploy the add-in in ArcMap 10.1? I have just tried that and ArcMap 10.1 crashed.
To give you some context, my dev machine runs ArcDesktop 10.2.2 but I'm developing extensions for an organisation that has ArcDestop 10.1 only. What is the best practice in such circumstances?