ngx-dropzone-wrapper: Build with aot error with css and js files not found

Running ng serve works perfect. If I build the app for production it gives me error-

ERROR in ./~/angular2-dropzone-wrapper/dist/lib/dropzone.component.js
Module not found: Error: Can't resolve 'dropzone' in '/Users/sunnygupta/Sites/customer/node_modules/angular2-dropzone-wrapper/dist/lib'
 @ ./~/angular2-dropzone-wrapper/dist/lib/dropzone.component.js 2:15-34
 @ ./~/angular2-dropzone-wrapper/dist/lib/index.js
 @ ./~/angular2-dropzone-wrapper/dist/index.js
 @ ./src/app/app.module.ts
 @ ./src/app/index.ts
 @ ./src/main.ts
 @ multi main

ERROR in ./~/angular2-dropzone-wrapper/dist/lib/dropzone.directive.js
Module not found: Error: Can't resolve 'dropzone' in '/Users/sunnygupta/Sites/customer/node_modules/angular2-dropzone-wrapper/dist/lib'
 @ ./~/angular2-dropzone-wrapper/dist/lib/dropzone.directive.js 2:15-34
 @ ./~/angular2-dropzone-wrapper/dist/lib/index.js
 @ ./~/angular2-dropzone-wrapper/dist/index.js
 @ ./src/app/app.module.ts
 @ ./src/app/index.ts
 @ ./src/main.ts
 @ multi main

Temporary solution I found was copying and pasting the dropzone folder from /node_modules to /node_modules/angular2-dropzone-wrapper/node_modules/