As the subject shows, experience really, really slow interactive render viewport regression/update with your latest version and corona 7.
That has been an issue in the past with ever since version 7 was presented and was forced me to switch to earlier version 6 as the "automatic" camera clipping just does not work well. For some reason version 7.1.2 was way smoother than 7.3.
As far as can see version 7.3 you enforce every single FP to use "aumatically" cameras for clipping. That's terrible decision, especially considering the clipping features with Forest pack are known for years for bringing huge viewport /fps regression.
How come the clipping is automatic now? What is the point? It might work for fairly simple scenes, but do you understand what nightmare it becomes when one opens a scene with 20+ Forest packs for revision?
Going to switch back to previously working version, which did not give so much trouble and will write if experience the same issue!