Hi, welcome to forum and thanks for kind feedback
Playlists in free Splash Lite are limited.
The order of the playlist item will be exactly the same as the order in windows explorer.
If you have items sorted by size in windows explorer and select it and drag and drop to Splash then it should keep the order from windows explorer.
Please be sure to perform drag and drop with the top/first selected file. Then the order will be kept. Otherwise the first item in Splash playlist will be the one that was selected when drag'n'dropping.
Unlimited full-featured playlists will be available in Splash PRO, HD-Cam and other commercial products.