Personally I wouldnt use CA glue, it dries way to fast for me. I use Model mast liquid cement.
Assemble them in small groups and then add the groups together. Aslo, asseble them on a straight edge like a ruler or strup styrene. This wiil ensure that you make them sraight. And last thing, After you have glued the tracks in some sections, before they completely dry, lay them on the road wheels so that athey can set overnight. this will form them into the proper shape.
it takes patience but you will be happy with the results.