I have exactly the same Tile Map visualization (Shaded Circle Markers), once on Kibana 5.3.0 and once on Kibana 5.4.0.
The Tile Maps use external WMS source.
In Kibana 5.4.0, the zoom is restricted to a certain level, after that no more zooming in is possible.
The same problem occurs with other WMS sources, with heat maps as well as with the standard OpenStreetMap source.
Do I have to set something like
tilemap.options.maxZoom: 18 in kibana.yml?