Minecraft version
1.16.4

Mod version and malilib version

• litematica-fabric-1.16.4-0.0.0-dev.20201103.184101.jar
• malilib-fabric-1.16.4-0.10.0-dev.21+arne.2.jar

Description of the bug
When trying to load certain schematics, the game will say "failed to load" when I try to load it. These are the ones I am currently trying to load, but there are many more than these.

• https://www.planetminecraft.com/project/new-delta-hq-concept/
• https://www.planetminecraft.com/project/huge-modern-mountain-house/

(Edited by masa: cleaned up, removed the issue template stuff.)

The schematic from the first link is in the Sponge schematic format. That format is currently only supported in the 1.12.2 version of Litematica, but that support will come to the other versions in the next month or two, hopefully. The second link is just a world download, so not related to Litematica.

this file in format. schematic, cannot be loaded either!
https://www.minecraft-schematics.com/schematic/15661/#

@lllWinchesterlll That file is also in the new Sponge format and should preferably be named *.schem. I guess that site just does not support other file name extensions than *.schematic, which is unfortunate, since it creates a lot of confusion between the old MCEdit/Schematica format and the new Sponge format, which have a totally different data structure internally.

So currently you would need to paste it to a temporary world with World Edit and then save it from that with Litematica.
Here is a quick howto on that: #265 (comment)