Mostly, if you haven’t added any new field to the Product & Product Variant you can surely use our extension to integrate Solr to your customized nopCommerce store. However, if you have customized Product, Product Variant or Catalog pages, just drop us an email with details of customization and we’ll be able to inform you whether you can use it or not. Moreover, we do offer a special license with access to Source Code of the plugin. Please contact us for more details of the same.