Or use the auto-deploy which automatically joins the server for you when there's a free slot.or spend the best part of 2-20 mins alternating clicks on the NWA server in the list hoping for someone to disconnect.
FYI: Click chosen server ---> Server Info ---> Auto-deploy ---> If I remember right NWA is 62/64 (2)
In other words maxed at 62 with 2 reserve, in which case put the minimum players in the auto-deploy options to 61 and as soon as this is reached it will attempt to join for you, doesn't always work but better than what you described.