[OSGeo Africa] Adding NGI topomaps as a gdal layer in QGIS

[admire]

Hi All

I am trying to use the XYZ tiles from 
https://htonl.dev.openstreetmap.org/ngi-tiles/tiles/50k/{z}/{x}/{-y}.png 
in QGIS Web Client.

However, the web clients have some limitations with loading this as 
native XYZ tiles.  So I have reverted to  loading the XYZ tile as native 
gdal layer in QGIS but I cannot get the syntax correct for the xml. Is 
there anyone who has done it for this layer ?.

I can load the Aerial Imagery fine using an XML but have been 
unsuccessful in doing the same with topo sheets.

Regards

Admire