Start Interactive button remains inactive

[cgiout]

3ds max 2015 x64 SP2
Build 18-03-2015

Starting Interactive Rendering in Corona VFB and the stopping it or closing VFB window makes the button in the scene tab remaining disabled.
Closing & Opening the Render Setup window makes it turn to selectable again.

Is it normal or is it a bug?

[maru]

I can confirm this.
max 2015, 18-03-2015

[Ondra]

Fixed, good find