Package is busted, lacks the JS and CSS files. 6.0.9 is the last functional version.
If you mean the GPL package - yep, I can confirm the issue, we will publish the functional version as soon as possible. For now you can download the 6.1.4 GPL from Webix site.
At the same time Pro packages seem to be correct in npm.
Webix 6.1.5 GPL is already available with the mentioned package bug fixed.
BTW, the What's New lost the markdown formatting for the recent versions:
It looks like you're new here. If you want to get involved, click one of these buttons!