Im unsure whats causing this, but on the 1.16.5 version on forge version 36.1.0 when respawning or reentering a created world with a belt in place, the world crashes along with the game due to a ticking tile entity. I havent had this issue before with the mod, either alone or with others, however i have installed other mods along side create. ive attached the crash log to the issue in hopes it sheds some light on the matter
crash-2021-03-30_02.15.39-client.txt

This issue has been marked as stale because it has been inactive for 3 weeks. It will be closed if it remains inactive for another 3 weeks.

This issue has been closed since it has been inactive for 3 weeks since it was marked as stale.

Try updating Optifine to 1.16.5 U G7. I believe the version you're using, 1.16.4 U G6, has stability issues.