The constant embers on screen were unintentional, primarily due to the special effects crew unfamiliarity with Adobe After Effects.
Eric Roberts nickname on set was Eric Robots.
At 21:48, two payphones were glued together with a Velcro strap to create the cyber-Abraham-Lincoln mouth piece look.
The fight scene between Trikalypse and Jankins was shot on the set of storage wars.
At 17:30 you can see the equipment truck in the background of the fight.