Using Fabric for a Blocking Dialog with Overlay

I hope this is the right place to ask this question. I am new to developing for Office 365/SharePoint Online, though I have worked for years with on-premise SharePoint 2010 and 2013. If this is the wrong place could someone suggest an alternative.

For the home page of a SharePoint.com site I am creating a “compliance check” function. Users need to acknowledge that they confirm their compliance and optionally opt in to email alerts. I think this is a good opportunity – a learning one for me certainly – to use the Office UI Fabric, and I will add a rest api query to a list. I have made a start based on the examples of Overlay and Dialog shown on https://dev.office.com/fabric-js/Components/Dialog/Dialog.html and https://dev.office.com/fabric-js/Components/Overlay/Overlay.html

I am using a content editor web part on the home page to load HTML and JavaScript from a text file. In the file I am creating a dark overlay and a blocking dialog. I have two problems:

• the page keeps refreshing every few seconds
• the dialog doesn’t block the user from interacting with other components on the page, e.g. links to folders in a document library

Can anybody offer some insight into that?

Thanks,
Tom