Randi Kleiner felt like an 8-year-old at her birthday party as she fretted inside the Sie FilmCenter. It was 2015, the opening year of the SeriesFest TV festival and, as with a birthday party, there was no guarantee people were going to show up. ” ‘Is anyone actually coming?’ ” the festival co-creator recalled wondering as she unlocked the doors at the theater on East Colfax Avenue.