If you're still having problems with this, make sure that you've DL'd the correct POL for your area, I DL'd the US by mistake not the EU one, and I got the same message you did about it not being installed when I tried to get the game to run
I would say no it's not too late to start, I solo a lot (due to unsocial hours and low play time) and I see new players going through the starting areas all the time, some of them maybe new characters for old players but I doubt all of them are