Start parameters for templates and more

Each template now has a set of start parameters you can customize.

New templates

Compact Disc
Trip
CDJ-4000

Improved video backgrounds

The UI of the video background editor has been improved.

Added preview image for the video
Added Play video from parameter

Improved performance

A lot of performance issues that were causing the editor re-download all the assets every time you open the project got fixed. By leveraging the browser cache, we've made the editor load much faster and use less network bandwidth.