Angular 5: unmet peer dependancy @angular/core@^2.0.0

[superkick]

Hi,

Using the following Angular config:

Angular CLI: 1.6.8
Node: 6.11.3
OS: darwin x64
Angular: 5.2.5
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, platform-server, router

angular/cli: 1.6.8
angular-devkit/build-optimizer: 0.0.42
angular-devkit/core: 0.0.29
angular-devkit/schematics: 0.0.52
ngtools/json-schema: 1.1.0
ngtools/webpack: 1.9.8
schematics/angular: 0.1.17
typescript: 2.6.2
webpack: 3.10.0

I get the following NPM error:
bergben-angular2-file-drop@0.2.0 requires a peer of @angular/core@^2.0.0 but none was installed.

How can I satisfy this using @angular/core@5.2.5?

Many thanks.