Is it better to add files from Built-in Storage or execute the playlist from network storage?

Either way is possible. But please note that the storage should be fast enough for reading video files in real time. So in case if the files are stored in the local drive - it is important to ensure it can provide a good reading performance, especially it is important for HD video with high bit rates. It is not recommended to store the video files in the system drive (disk C), it's better to get a separate drive.

In case if the files are located in the network storage - in order to exclude any problems with network connection, we recommend to enable the Proxy functionality. For this you should have a proxy drive which should be able to provide a good enough reading and writing performance simultaneously. The recommendation is to have the separate physical drive for proxy, preferably several disks joined into a fast RAID array (raid 0 or 0+1), read more recommendations for Proxy drive in the Cinegy System Recommendations document.