HANA Express : XSA Build Error hdi-builder is not available for workspace

Hello,

I am running HANA Express 1.0 on AWS. I was following the sample application build blog . While building the HDB module I am getting the error which says "hdi-builder is not available for workspace workspaceXXXXXXXX " . I followed the comments on the blog but could not resolve the issue. So far I have done the following:

1. xs apps command tells me that all the apps including di-core are running under space SAP. I have tried to restart the di-core.
2. I have set the dev space to SAP. I have assigned my user XSA_DEV the SpaceDeveloper for same space.
3. I have rebuilt the app 3-4 times from scratch to make sure di-builder gets redeployed.
4. I have tried restarting HDB and rebuilding the app.

Any idea what the next steps should be?