I just updated the following anchorages:
Luckily, in Istria the port authorities provide pretty detailed information about their anchorages.Quite interesting is the Port Authority of Umag-Novigrad, they have a fully digitalized management of port operations and services, including a berth booking system, called "SmartPort". You can find the documentation of this system here. SmartPort is used only by port authorities themselves, but you can use the read access directly, to see the actual berthing status of the ports.