This was originally posted in Trouble connecting to cesium asset - #4 by Mathieuvannereux , and the part that said
When i click on “Authorize access”, Unreal crash …
was one reason why I suggested to open a new thread here (it should not crash, no matter what the underlying reason for the error is…). The other reason is that the missing menu that you’ve been talking about. (Hopefully, that can be sorted out here).
A first step for analyzing the issue in terms of what might be related to Cesium ion or your token would be to look at your assets page and see whether the asset with the right asset ID is listed there, and your tokens page to see whether the right token is used.