This is the same issue that i add (and i closed it by accident sorry)
So plan9k issue panic occured when i want to install and got [Java]:in?
i will try to give the footage and the version (maybe i cant show the logs because its too long)

Also i use pojavlauncher (i dont know if the issue can be removed with using a pojavlauncher)

Footage:https://imgur.com/a/jgToJQO
Minecraft Version:1.12.2
Opencomputers Version(if necessary):New version (created in jan,6,2025)

looks like an error in the toHex() function, and more precisely Lua doesn't seem to know what the shift operator (>>) is...
The problem is, it doesn't make any sense as it is mentioned in the reference manual as a bitwise operator like any other, so the only thing I can see is that something's wrong with the mod/Lua. Try deleting the DLLs at the root of the Minecraft instance and reinstalling the mod (including deleting the config).

You need to use Lua 5.3. Shift-right-click on the CPU to change its Lua version.