Hi,
Most likely, the issue is caused by a module you have enabled on that world that you don’t have on the other. I suggest you first try to disable all modules and see if that solves it, then you can start enabling them in small groups until you find the one that is causing the problem. If the issue is that easy to reproduce for you, you can use the module “Find The Culprit” to help you more easily find which module is causing the problem.
You can also check this thread for list of known modules that work on 0.7.5 (the latest stable) and which modules are problematic : What modules work in 0.7.5?
I hope that helps.