I’ve got a schema with 73 tables (average 15 columns each). It took me 2 hours to run Tables and Columns report before I was even able to generate PDF file. It goes through 2 stages: setting up report, gathering data, generating and formatting. The first 2 are almost instantaneous. The last 2 are extremely slow. In addition I can’t use Nav anymore because It does not let me to open or switch to another session.
I have to start another instance of Nav to continue.