Windows .exe My dw20 1.6.4 will stay on the Mojang screen but after a bit it just closes

[Dessy]

I have been able to launch it before, but when I updated it last it starts to launch but closes at the Mojang screen. here is my log:http://pastebin.com/9bNRdQ8q

 

[JamiePhonic]

do a force update to v 1.0.11 (there was a mistake in 1.0.10 with Calclavia Core adding worldgen

Caused by: java.lang.RuntimeException: Unknown character '
2014-01-16 10:35:43 [INFO] [STDOUT] [Calclavia Core] Transforming Chunk class for chunkModified event.