no, there is not official support currently. Magic Dosbox works well with shield tv, however is not fully controllable with remote controller, that’s why google blocks it. However I can help you, just send me email.
For anyone, be patient. We are working on that, but it is terrible lot of work and will not be finished in near future. Currently main menu is 100% rewritten, in game interface is done around 30%. Virtual keyboard was not compatible with console systems and we work hardly on new implementation which could be released in next update. Small preview :