Metacheck has no specific installation procedure. It may be used in several different ways using ant.
Best practice for now is to integrate metacheck in the build procedure of your java project. Unpack metacheck.jar from either the binary or the source jar. Put the metacheck.jar somewhere in your projects classpath, modify your build.xml to include one or more metacheck tasks or use a separate build file. Note that for some code checking tools additional config files are required.
For just an occasional metacheck of your project, put metacheck.jar and dom4j.jar in a lib/ subdirectory, put jcsc and checkstyle rules files in the etc/ subdirectory and analyse.xml in the top-level of your project. Some minor modifications to the analyse script will be necessary, to get metacheck to work.