liferay-6.1.1-virgo-wab.zip - contains all these directories in one useful for downloading archive. If you download liferay-6.1.1-virgo-wab.zip you don't need to download all other files.
To avoid conflicts you should delete "org.eclipse.virgo.apps.splash_3.6.0.RELEASE.jar" and "org.eclipse.virgo.apps.repository_3.6.0.RELEASE.par" from the pickup directory of your Virgo installation.
WARNING!!! All applications and libraries have been published here were not seriously tested and show very low performance on Virgo, that is why I don't recommend to use them in a production development. But you can use them in any testing, research, measurement, learning and other purposes freely.