I worked on Twinmotion for a while and I missed pivoting the camera when I click the left mouse button. It makes editing in the viewport a lot easier.
I understand how important smooth camera control is for editing. If left mouse clicking to pivot the camera is missing in Twinmotion, you might want to check the control settings to see if there’s an option to enable it. Some software allows customization for mouse clicking functions, so adjusting the keybindings might help. Hopefully, a future update brings more flexibility for camera movement