Provide at least the following information

• Minecraft version - Which Minecraft version are you playing on?
• 1.18.2
• Mod version and malilib version - Which exact mod version are you using?
• malilib-fabric-1.18.2-0.12.0
  • Include the full mod file name which includes the build date and time for the development versions, or you can see the mod version in the title of the Litematica main menu.
  • litematica-fabric-1.18.2-0.11.0
  • "Latest" is not a version!! It's ambiguous, it's a moving target, and very often the version is not actually even the latest available version at that time.
• A clear description of the issue - I'm not a psychic, so you have to describe the issue thoroughly enough for me to be able to reproduce it without knowing anything at all that is not described in the issue report.

The game crashed as I tried placing my schematic that I took from Scicraft -> https://ufile.io/eaxflgdu
Error log -> https://pastebin.com/mf6P3qP1

java.lang.ClassCastException: class fi.dy.masa.litematica.world.WorldSchematic cannot be cast to class net.minecraft.class_638 (fi.dy.masa.litematica.world.WorldSchematic and net.minecraft.class_638 are in unnamed module of loader net.fabricmc.loader.impl.launch.knot.KnotClassLoader @604c5de8)
    at shcm.shsupercm.fabric.citresewn.ActiveCITs.getItemModelCached(ActiveCITs.java:137)

That's the CITResewn mod trying to cast the schematic world into a ClientWorld without checking first that it is one (which it's not).

Looks to be fixed in a later version of CITResewn.