Are you saying it was too slow on the larger map? That can make things seem uncertain. Other than that things should behave the same way if you do them the same way between maps.

If things are slow now before you ever add anything but the land, then it could be that you have too many nodes for comfort. The problem only multiplies as you add terrain and trace along the existing coastline for the edge. If this is ringing true to what you are seeing, I recommend using the SIMPLIFY keyboard command to reduce the total number of nodes. You would be surprised just how many of the nodes in a coastline don't actually do anything because they are too close together to be noticeable.

If the lines are already drawn you can use Change Properties to give the lines a line width if they have none, or to make the line width thicker. Rather than guessing how thick the line is to start with, you can use List from the Info menu to find out how thick the line is before you start.

There's a loop in the line at that point. If you look at it as if it was a road you were driving down starting from the left, when you get to that point you are heading to the northernmost point first, and then the southern point second. Jim is right - you just need to decide which of those points is the one you want and delete the other one using the delete node tool |CC2DELNODE|.

If you are having trouble hitting the point it's not at the very tip of the line because the line has a width. The nodes are in the centre of the line width, so it will be a short distance in from the tip of the point.

Oh no, definitely not! This thread is one of the first I check each morning :)

Use List in the Info menu to find out how many nodes you have in that large landmass. It's the node count that really slows CC3 down. over 10,000 is where it starts to get slow, while 30,000 is nearly impossible to work with. But do you really need that many? In most cases, not really.

If you can get away with it without losing something important, use SIMPLIFY to get rid of unnecessary nodes. Even if you use a very small factor with SIMPLIFY, it will still get rid of any nodes that are right on top of each other and not really doing much because they are too close to make any difference.

Fractalise is a high risk tool to use. If you use it too many times all you end up doing is making the coastline frilly and CC3 slow, neither of which are good things. I don't recommend fractalising anything large more than twice with the default settings and definitely no more than 3 times. You also have to consider that however many nodes you end up with in the coastline you will double that if you then trace the coastline with all your terrain fills.

If you want to be able to edit and trace your coastline, use a colour key for the central ocean instead of multipolying the two parts. A multipoly can't be traced, edited, or fractalised.