Ah. I see. I didn't notice at first that the blobby lake down there connected to the edge of the map.

Yeah RPGCMG has problems with rivers and roads. I'm not saying I could do better but it's pretty borked. Still, it gives a good foundation for some judicious editing. I've made some maps I'm pretty happy with using it...in particular Brushy, KS and Ruins of Ningan on my gallery. There are a few more in there I did using it as well.