Per the wiki:
This black screen is a bug with 1.0. Patching from 1.0 to 1.11 cause this error to resurface.
To fix it, you need to install patch 1.01 before installing 1.11 (if you already install 1.11, need to uninstall, install 1.0 > 1.01 > 1.11 would fix it).
To get the old 1.01 patch, simply copy and change the URL (from 111 to 101) at where you download the patch.
Patch 1.12 is out, it includes the ch.2 black screen fix and no longer require installation of 1.01.
Update: 1.12 introduced a save/load bug... so don't install it. If you already installed 1.12, can overwrite it by running 1.11 patch again (1.11 does not check for previous version)