Welcome to the TextUML Toolkit update site. This site contains feature and plug-in versions for TextUML Toolkit releases, published in the form expected by the Eclipse Update Manager. Use the Update Manager to open this site (http://abstratt.com/textuml/update/) and locate new and updated feature versions of the TextUML Toolkit to install.
If you are not familiar with installing features using the Eclipse Update Manager, please read this. If you still need help, ask on the TextUML Toolkit user forums.
If you don't have Eclipse installed, you can also download the full TextUML Toolkit (including the Eclipse Platform) as a single file.