I think there are two ways you can do it.
1. Set the actuator type to standard on the nano dimmer.
Then when you highlight the analogue output there should be a fade rate setting. i believe there should be a setting called jump that should make it fade instantly.
Also make sure you set a type of dimming to something other than off.
I don't think this will work properly with the new lighting controller but should work fine with a simple on/off switch
I believe the second way to do it is how Loxone intended the new lighting controller to work.
2. set the nano dimmer air to smart actuator and choose a type of dimming.
on the lighting controller block properties under parameters there should be two parameters SI and ST playing around with these I think will change how fast the light dims up and down.
Just play around with it.