To link existing trailers to a series:
Click MANAGE TRAILERS.
Click the blue (plus) icon beside the required trailer.
The added trailer moves to the Linked Trailers list on the right.
To add more trailers, repeat the process.
When all required trailers have been added to the Linked Trailers list, click SAVE.
The linked trailers are now visible in the Trailers tab for the series.
