its 30-40 sec on their templates list. BUT once i open them to edit, they are becoming 15-18 seconds editable, wich is too short with inapropriate lenght...
. . . . why are the movie templates 15 secs when downloaded to edit, but the demo templates are 30-40 seconds . . . .
To avoid confusion please use the correct names for the Templates you are referring to - Movie templates and Editing templates are 2 different features.
Movie Templates cannot be adjusted for length until they are actually 'disconnected' from the template which reverts to project to Timeline mode for further editing.
What you are referring to are the Editing templates which do have different selectable lengths and are very similar to the Movie Templates and can also be disconnected from the template for further editing in Timeline mode.
If you want to do further editing on either type, click the tick mark top right of the template pane after adding the video/images.
This will display the project in timeline mode - note once disconnected from the template there is no going back to editing the template in that project.