Image automation should preserve the layer system that made the original design work. The template contract changes copy and media without flattening masks, gradients or palettes.
Build for real content ranges
Test short and long headlines, missing optional media and the actual aspect ratios promised by the campaign.
Reference media by project ID
Upload the campaign media once and bind the returned image reference. Avoid embedding large data strings in every template fill.
Choose the output deliberately
Use PNG or WebP when transparency matters and JPEG for photographic delivery when alpha is not required.