Facing issue in converting ngx-admin into library

Hi,
I want to convert ngx-admin into library and then use it into my project. I tried to do this with ng-packagr but at the time of build its throwing error in index.js of nebular saying cannot read the file or file not present. Please help me on this. I used this link and followed the steps
https://medium.com/@ngl817/building-an-angular-4-component-library-with-the-angular-cli-and-ng-packagr-53b2ade0701e