Yep. The theme definition for the link column wasn’t checked in. Will be in the next update.
If you use linkColumn1.LinkBehavior = LinkBehavior.AlwaysUnderline or LinkBehavior.HoverUnderline it should show the underlined link.
When you click it, you still get the CellClick event, it’s not a real link, it’s a cell renderer.
I had used the AlwaysUnderline, with no effect, it does work with the the HoverUnderline. A minor effect I noticed here is that once you click on a link cell (which is underlined since you are over it) the underline doesn’t show again on that cell till you click in another row.