Selecting assets
To select a file to download, just click on the file in the gallery view to select it. In the grid view, just select the asset by ticking the box on the left-hand side (next to the asset preview).
To bulk select, just hold shift and click on multiple files, or lasso-select a group of assets (in the gallery view). In the grid view, just click on multiple files by ticking the boxes, or hold shift and click on an asset further down to select a larger group of assets.
Downloading
Once you have selected the files, a menu will pop up at the bottom of your screen. From there, click on the download button to start the download.
If you have selected multiple files, they will be downloaded as a .zip file.
Downloading custom sizes
If you select individual files to download, you have some additional options on how to download it. You can choose to download the original file, or to download a cropped version in another aspect ratio.
If you want to add a custom resolution to this menu, you can do that under settings -> available options.