I’ll start by outlining this issue in that I have confirmed that both Immersive Engineering and JurassiCraft work fine when running the same modpack in singleplayer or hosting the server without Sponge installed.
The issues are:
JurassiCraft: Dinosaurs do not age, confirmed via NBTedit and checking the “dinosaurage” NBT that the number does not go up. This only happens when sponge is installed
Immersive Engineering: Blocks are not updating their textures/rotations properly. When using the engineer’s hammer to rotate or change the input/output of a block it does not update unless you manually update the block by placing another block near/on it.
Minecraft version 1.12.2
Forge Version: 1.12.2 - 184.108.40.20644
Sponge Version: spongeforge-1.12.2-2838-7.1.7-RC3908