You are having framedrops and your game is lagging? There are many factors that can create this issue. The first step, if it is possible, is to downgrade your version. So if you use 3D CreatorCraft Ultra, think about using 3D CreatorCraft High for example...
Since 3D CreatorCraft uses many 3D models, another problem can be the world you are playing on. If you are using 3D CreatorCraft Ultra and the whole world is made out of cobblestone, which is a 3D model with a big file size, your game will eventually crash, since 3D CreatorCraft is not designed for such situations. So the minecraft world you are playing on also plays a big role.
The next issue can be mods in general and also OptiFine. Generally OptiFine is recommended for 3D CreatorCraft, since it improves the performance, but some settings in OptiFine can also cause problems, such as Dynamic Lighting, which allows the player to create light in his environment while holding a torch in his hand. Since there are many light updates going on, performance issues can be created, when those light updates apply to a model with a big file size such as cobblestone. So your game may lag while walking with a torch in your hand over cobblestone. So dynamic lighting should be turned off.
Now additionally to improve the performance you can turn off ambient occlusion, which creates the shadows in minecraft vanilla. To do this go to options > video settings > smooth lighting and turn it off. This should solve the performance issues caused by light updates.
You can always also reduce your render distance of course.
Never use 3D CreatorCraft in Minecraft versions, that are not supported such as Minecraft 1.8. Always check if you are using the right Minecraft version.
The above said about Framedrops while using 3D CreatorCraft also applies to 3D Seasons.
To use 3D Seasons (1.13) you have to install 3D CreatorCraft too and make sure that 3D Seasons is on top of 3D CreatorCraft. If you are not sure how to install 3D Seasons correctly, check out this guide.
Are you sure, since they 20 minutes to change. If you are not sure you can download 3D Seasons Test and test the seasons change, since they should than change in seconds.
The above said about Framedrops while using 3D CreatorCraft also applies to 3D Noteblock Displays.