Your colors are very bright! These maps have a certain charm, although I'll note that from a realism perspective, you've got some river violations (rivers join as they flow to the sea, they don't split; lakes have only one outgoing river) and the city has an implausibly large amount of open space. I don't know a thing about using Corel, and it isn't a common choice around here, but you can get a lot of useful advice that isn't program specific.