Q Light Controller+

I am looking for a ceiling mountable on-by-default light after powercycle that can also be controlled through DMX to switch it off.
It would be light if it could be flush cei8ling mount like this..
https://www.ebay.com/itm/DJ-Par-Light-P ... SwbF1blsvm
Any such thing exists ? It should be white only, but is ok if it is RGB.

Try to find a fixture where you can set it's state when there is no DMX signal present.
Set it to full white under the 'no DMX signal' condition.
After the system boots DMX signal will be present so the first thing to send is a full white scene. (Look for the green flag or the autostart function)
http://www.qlcplus.org/forum/viewtopic.php?t=9209