Structures with Custom Block and Chests

Issue description

So, I am making a Structure with .Schematic with custom blocks and Fluids, also some with Loot chests inside them but when I add the Element for the structure, The custom blocks/fluids become pressure plates, redstone torches and other vanilla blocks, also Loot chests are empty, note that I filled the chests with items before export schematics, well I need help to solve this, or this Bug... What can I do?

Issue comments

.shcematic file format is outdated in Minecraft world and so is in MCreator. We won't improve schematic support. You should use .nbt structure block format instead. It supports all block, item and entity data and is much more versatile and easy to use.

Use the structure block. It is a vanilla block that can be obtained by using  commandos like /give @p structure_block. Go the official minecraft wiki to see how does it work.