B4J Question jGoogleMaps Version 1.82 problem

I have used jGoogleMaps Version 1.25 with B4J Version 6.51 successfully for a long time. Now I want to move to the actual B4J Version 8.50 and the actual jGoogleMaps Version 1.82 and get an error. To analyse the problem I have startet the actual GoogleMapsExample and get the same error. After starting the map shows up, but within a second it disappears. After using the "Reset Map"-Button the program terminates.
In the java console I can read:
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Alert: loadMapLibrary
mapLibraryLoaded!
Alert: !!!mapLibraryLoaded!!!

main._btnresetmap_action (java line: 109)
java.lang.NullPointerException
at com.lynden.gmapsfx.javascript.object.GoogleMap.internalGetZoom(GoogleMap.java:76)
at com.lynden.gmapsfx.javascript.object.GoogleMap.zoomProperty(GoogleMap.java:93)
at com.lynden.gmapsfx.javascript.object.GoogleMap.setZoom(GoogleMap.java:68)
at anywheresoftware.b4j.googlemaps.GoogleMapWrapper.MoveCamera(GoogleMapWrapper.java:239)
at b4j.google.map.main._btnresetmap_action(main.java:109)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
at anywheresoftware.b4a.BA$1.run(BA.java:216)
at com.sun.javafx.application.PlatformImpl.lambda$null$5(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$6(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$4(WinApplication.java:186)
at java.lang.Thread.run(Unknown Source)
---
I used a valid API Key and Java Version 1.8.0_231.

Any Idea to solve the problem?
Thanks,

R