I know it's been awhile and we've talked since then but I've just stumbled upon your question here and just in case, wanted to double check if it's still relevant. Also, maybe it could be useful for others, too. We typically recommend the following approach when having issues:

• checking the docs on https://xeokit.io/

• trying to reproduce with https://xeo.vision/

• getting support either by contacting us directly (email, Service Desk for customers) or through the xeokit Community on GitHub: https://github.com/xeokit/xeokit-sdk