You need to do the proforma the clients from the 2018 program. In the 2019 program press F10 and look at system file path. When in 2018, do another proforma and verify the system file path for 2019. 

I would NOT do all of them now, as the program is notorious for having many flaws this early in the game. I do my return only and start to play with it for this year. There are also demo clients you can access from a RESTORE from C:\LACERTE\19TAX\DEMODATA\ that are a good practice. Be sure the SSN (or EIN) is all 9's and there will be no REP charge. 

You also do the Organizer for 2019 from the 2018 program. I would NOT do all of them now, as the program is notorious for having many flaws this early in the game.