I just had some trouble with opening LibreOffice after reinstalling my machine. Apparently, the cause of the problem is simple. After reinstalling I ditched the old Java 6 u 29 I had and only installed Java 7. The result was = reproducible crash of LibreOffice directly after opening LibreOffice/Writer. Downloading Java 6 u 30 and doing a side by side installation with Java 7 resolved the problem. Everything is running smooth again.
I suggest to change the wording on the main page to "Requires Java 6" (erase "or later") until the problem has been addressed.
OS: Windows 7 x64 English
JRE: Java 7 u 2
Office: LibreOffice 3.4.5 (win32)