It looks like MSVC cl.exe is not being found, but not sure...
[Tue Jun 20 20:09:01 BST 2023][INFO] We will now compile your code for x86_64-microsoft-windows. This may take some time.
java.io.IOException: Cannot run program "cl" (in directory "FULL_PATH_REDACTED\gluon-samples\HelloFX\target\gluonfx\x86_64-windows\gvm\HelloFX"): CreateProcess error=2, The system cannot find the file specified
at java.base/java.lang.ProcessBuilder.start(ProcessBuilder.java:1143)
at java.base/java.lang.ProcessBuilder.start(ProcessBuilder.java:1073)
at com.gluonhq.substrate.util.ProcessRunner.setupProcess(ProcessRunner.java:378)
at com.gluonhq.substrate.util.ProcessRunner.runProcess(ProcessRunner.java:236)
at com.gluonhq.substrate.target.AbstractTargetConfiguration.compileAdditionalSources(AbstractTargetConfiguration.java:357)
at com.gluonhq.substrate.target.AbstractTargetConfiguration.compile(AbstractTargetConfiguration.java:134)
at com.gluonhq.substrate.SubstrateDispatcher.nativeCompile(SubstrateDispatcher.java:425)
at com.gluonhq.NativeCompileMojo.execute(NativeCompileMojo.java:54)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:137)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:210)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:156)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:148)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:56)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:305)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:192)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:105)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:972)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:293)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:196)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:282)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:225)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:406)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:347)
Caused by: java.io.IOException: CreateProcess error=2, The system cannot find the file specified
at java.base/java.lang.ProcessImpl.create(Native Method)
at java.base/java.lang.ProcessImpl.<init>(ProcessImpl.java:494)
at java.base/java.lang.ProcessImpl.start(ProcessImpl.java:159)
at java.base/java.lang.ProcessBuilder.start(ProcessBuilder.java:1110)
It looks like MSVC cl.exe is not being found, but not sure...