Since many custom maps (especially the CS maps) use tons of custom images, I'm suggesting that all of the needed images get compressed into a single file, transferred, then uncompressed. This would save time and bandwidth at the negligible expense of CPU and drive space.
Obviously if Soldat uncompressed directly into the Soldat folder, issues would arise (like overwriting default scenery and other files). Instead it should uncompress into a temporary folder then move the scenery files one at a time as it checks for such issues.
One more time:- Host sends map
- Client asks for images
- Host compresses, sends packed images
- Client uncompresses packed images into temp folder
- Client moves images to rightful places