Unable to build for android using the Backendless SDK

Attempts to deploy to an android emulator fails with the following message:

warning: [options] source value 8 is obsolete and will be removed in a future release
warning: [options] target value 8 is obsolete and will be removed in a future release
warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
/Users/~/.pub-cache/hosted/pub.dev/backendless_sdk-7.3.8/android/src/main/java/com/backendless/backendless_sdk/BackendlessSdkPlugin.java:49: error: cannot find symbol
public static void registerWith(PluginRegistry.Registrar registrar) {
^
symbol: class Registrar
location: interface PluginRegistry
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error
3 warnings

FAILURE: Build failed with an exception.

  • What went wrong:
    Execution failed for task ‘:backendless_sdk:compileDebugJavaWithJavac’.

Compilation failed; see the compiler output below.
warning: [options] target value 8 is obsolete and will be removed in a future release
warning: [options] source value 8 is obsolete and will be removed in a future release
/Users/~/.pub-cache/hosted/pub.dev/backendless_sdk-7.3.8/android/src/main/java/com/backendless/backendless_sdk/BackendlessSdkPlugin.java:49: error: cannot find symbol
public static void registerWith(PluginRegistry.Registrar registrar) {
^
symbol: class Registrar
location: interface PluginRegistry
warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
Note: Recompile with -Xlint:unchecked for details.
Note: Some input files use unchecked or unsafe operations.
1 error
3 warnings

Attempts to follow documentation have failed. No “Downlaod Project Template” is available as no drop down menu exists as the “Quick Start Guide” page for the Flutter documentaion insists

Hi @Thomas_Loring ,

What Gradle/Maven artifact you used to connect Backendless SDK?

Regards, Andriy