Answered
BUG: Loudness Radar reset causes crash
I've reported this BUG: Loudness Radar reset causes crash – Adobe video & audio apps but maybe someone can check they get the same issue on their system?
Start new multitrack session
Add Special | Loudness Radar to master bus
Hit the 'reset' button (top right) on LR panel - CRASH
(it's the circle with an arrow above the Peak indicator)

