Make SURE you save it in the right map, sometimes if you don't it will load, but no bricks will appear/bricks will appear out of sight. That's all i know of, sorry if this didn't help. C:
you should know what you're talking about :D
so, you can save a file in any folder that's directly under saves (blockland/saves/name/file.bls), it just can't be a .zip or any other compressed file, you must have a .bls to be able to load it (the image is useful, but not 100% needed)
i have a folder inside maps that i created for DLed builds, which i find helpful
then when loading, click the map name at the top and change it to what you put it under, and load the file