Opening World Malfunction

Put the summary of the bug you're having here

What I expected to happen was...:
I very basically expected the world to open. Whether old or new worlds.

What actually happened was...:
Regardless of when I created the world, when it opens its as though the program is trying to open every skin and layout of the world possible. It usually only happens when creating a brand new world or trying to open another world after I've closed one. The music still plays, I am still able to move the character and presumable to perform actions (I can hear the noises). However, all around the different layouts and mobs and everything keep flashing and changing. I have to close down the entire game to get it to stop.

Steps to Reproduce:
1. Open program
2. Choose world
3. Close & save world
4. Choose or Create new world.
5. Open new world.