i think this is because construct 3 first load all project than run so i think your pre-loader is use less in this place go with default loader.
But i seen a problem with default loader is that it also load full project at first and then show default loading screen in between project loading default color of project .
construct team have to do something for this.
At least construct have to default loading bar in place of default color screen
Ashley if i am wrong please correct me .