If you have to conduct maintenance tasks on your own Diamo Velux then it is always recommended to have a Workshop Manual to keep just for a guide in case that you want to know ways to remove a particular part for example Wheel and install it again properly.
Diamo Velux Workshop Manuals provide you with particular diagnostic guides for the automobile so if something is broken it can help you determine what the issue is and some ways to fix it. You can then assess if this can be achieved by yourself or if ever the job is simply too big you can actually make a reservation for your Velux into a decent garage.
Diamo Velux manual