We’ve just released Wt 4.4.0 and Wt 3.7.0.
Among other things, this release adds support for multiple X axes to the 2D charts.
More information in the release notes.
Here are the links:
Wt 4.4.0: download wt-4.4.0.tar.gz (release notes)
Wt 3.7.0: download wt-3.7.0.tar.gz (release notes)
Binary builds for Windows are available on the GitHub releases page.