I don't think Nepal won the battle againts British. It surely wasn't easy for the British to take over or to calm Nepal down though. Nepal was in a lookout to extend it's border and met with British. Well after that, we all know, Nepal had to sign Suguli Treaty where it lost a lof of it's territory. And British were smart and strong enough to bully Nepal to get only the parts where they could benifit from. And also there is Nepal's defeat againts Tibet, which led Nepal to pay taxes to the Tibetean-Chinese empire up until early eighteenth century.