Example 'openwhisk-php-simple' not working

When deploying the example openwhisk-php-simple the following error occurs during deploy:

$ sls deploy
Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Compiling Functions...
Serverless: Compiling Packages...
Serverless: Compiling API Gateway definitions...
Serverless: Compiling Rules...
Serverless: Compiling Triggers & Feeds...
Serverless: Compiling Service Bindings...
Serverless: Deploying Functions...

  Error --------------------------------------------------

  Error: Missing mandatory openwhisk configuration property: OW_APIHOST. Check .wskprops file or set environment variable?
      at credentials.forEach.prop (\examples\openwhisk-php-simple\node_modules\serverless-openwhisk\provider\openwhiskProvider.js:47:15)
      at Array.forEach (<anonymous>)
      at hasValidCreds (\examples\openwhisk-php-simple\node_modules\serverless-openwhisk\provider\openwhiskProvider.js:45:17)
      at tryCatcher (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\util.js:16:23)
      at Promise._settlePromiseFromHandler (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\promise.js:547:31)
      at Promise._settlePromise (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\promise.js:604:18)
      at Promise._settlePromiseCtx (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\promise.js:641:10)
      at _drainQueueStep (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\async.js:97:12)
      at _drainQueue (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\async.js:86:9)
      at Async._drainQueues (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\async.js:102:5)
      at Immediate.Async.drainQueues [as _onImmediate] (\examples\openwhisk-php-simple\node_modules\bluebird\js\release\async.js:15:14)
      at runCallback (timers.js:705:18)
      at tryOnImmediate (timers.js:676:5)
      at processImmediate (timers.js:658:5)
      at process.topLevelDomainCallback (domain.js:120:23)

     For debugging logs, run again after setting the "SLS_DEBUG=*" environment variable.

  Get Support --------------------------------------------
     Docs:          docs.serverless.com
     Bugs:          github.com/serverless/serverless/issues
     Issues:        forum.serverless.com

  Your Environment Information ---------------------------
     Operating System:          win32
     Node Version:              10.14.2
     Framework Version:         1.61.3
     Plugin Version:            3.3.0
     SDK Version:               2.3.0
     Components Core Version:   1.1.2
     Components CLI Version:    1.4.0

Start in examples/openwhisk-php-simple and inspect its deployment configuration alongside the .wskprops or environment-variable setup mentioned by the error. Compare the example's requirements with serverless-openwhisk/provider/openwhiskProvider.js, then run sls deploy with valid credentials to confirm the example deploys without the missing OW_APIHOST error.