All of a sudden yesterday 3/4/2014 my MarkerWithLabel (Google map API application) is only showing the last marker but the labels all show up. It had been working just fine.
The most recent Google API update (4th APR 2018) has broken my version of MarkerWithLabel. I have not yet tested MarkerWithLabel 1.9.1, but it is still the current and most recent update (I was on an older build). Here is a link to the latest version:
https://github.com/googlemaps/v3-utility-library/tree/master/markerwithlabel
I have reverted to an older version by including &v=3.31 in the URL and this has restored functionality, many thanks to @Mikrohard for the tip.
I'm not moving until I've investigated if the update has broken other libraries such as map clusters.
It appears as if the latest google maps update broke something that markerwithlabel code relies on. The same thing happend to some of my maps. We'll have to wait until a fix is available.
The current solution is to set the google maps API version to 3.15 or lower: https://code.google.com/p/google-maps-utility-library-v3/issues/detail?id=296&sort=-id&colspec=ID%20Type%20Status%20Priority%20Fixed%20Owner%20Summary%20Stars