Freddie Mac announced this week further steps to move its secondary market transactions platform to the Internet. Guarantor executions for 15-, 20- and 30-year mortgages are now available to all lenders through the government-sponsored enterprise’s web-based selling system. Guarantor ARM and multilender executions will be available on the web system beginning Nov. 22, Freddie officials said. The transition to the Internet should boost lender staff productivity and lower the cost of executing secondary market transactions…