Hi German,
1 - If the plugin requires jquery 1.7.1, then it should work fine with DNN 7 as it uses jQuery v1.9.1 and usually plugs are forward compatible, although this one might not be the case;
2 - So make sure you don't make a reference to jquery 1.7.1 at all. The referent that already exists to jQuery v1.9.1 should suffice its needs;
It would be good if I could see the problem. Can you send the URL?
Also give it a try on this video I talk about jquery conflicts. It might be beneficial:
http://www.dnnhero.com/Premium/Tutori...
Best regards,