January 11, 2013, 11:20:07 am
Hi Chester Niziol, if you want a custom focal length in Build mode you need to set the Focal Length slider in a clip in Movie mode to the desired value and then click on the Build with effects button in the top left corner.
It is also supposed to work if you adjust the Focal Length in Photo mode and click on the Build with effects button in the top left corner, but there's currently a bug which prevents the Focal Length from being transferred correctly.
However, I expect this to be fixed in a future update.