Game crashes when using cauldrons in a preset.

What I expected to happen was...:
I was going to make a flatworld with only one layer of cauldrons as the floor. I thought that it was going to generate the world that I wanted.

What actually happened was...:
I entered this preset "2;1x118;4;", but my game crashed after I clicked "Use preset".

Steps to Reproduce:
1. Open flatworld preset
2. Type 2;1x118;4;
3. Click use preset
4. Game crashes