When running the server pack, the message
[Server thread/ERROR] [minecraft/WorldSettingsImport]: Error adding element: Base value out of range: 256 [-10-128]
Is printed every few seconds to many times a second.

Doesn't seem to affect the gameplay but seems to cause lag.

What could be the issue?

Shouldn't cause any lag, please provide more information:

• Modpack version
• Forge version
• Any additional mods you may have installed
• A game log

Closing issue due to no further information provided.

Hi, sorry for late reply.
Version: 2.1.0
Forge: 36.1.0
Additional mods: AppleSkin, JourneyMap and Create updated to v0.3.1
latest.log