To import an image sequence, in the Studio tap on Import and on Sequence.
Select the folder containing your image sequence and tap on Done.
Then the import windows lets you select the images you wish to import. All the images contained in the folder are selected by default.
You can import several folders at once, which will create a shot with a layer per folder.
To do so, select the parent folder of the group of folders you wish to import.
An image sequence can be imported directly from the shot by tapping on the import button at the top of the layers pile, and by following the same steps aforementioned.