World Stuck at Building Terrain

I visited the end for the first time and fell off the island and died in total darkness, I re-spawned on the surface and went back to the end to see if my resources were still there, as they weren't I jumped off the island to respawn again, but I did not respawn and was stuck in total darkness. I had to quit the game to get out of it. Now when I try to load up my world the Building Terrain progress bar stops at about 90% and it won't load. I was running a texture app called Clarity. I have tried uninstalling the game and re-installing it twice, I have tried loading the world with and without the Clarity Texture app installed but in all instances the progress bar reaches 90% and stops, I have let it run for 20 minutes but the progress bar does not move during that time. I can load an early 1st world OK but not my main 2nd world which I have invested many months in building. Help please.