What time does the mall open for Mall Walkers? And what entrance should we use?

They open at 8:00 and any of the entrances should work but it depends on where you want to go in the mall.

They unlock the doors at either 8 or 8:30. I used to work there, and people were there that early to walk. Any of the main entrances should be unlocked for you, but you can always call the mall office to ask.