I've been having an issue with some of my route sketches:

When a route sketch reaches a certain threshold of complexity (not sure if related to number of sketch segments, relations or both) a couple of things start to go haywire.  First, it becomes difficult to actually select spline segments.  Line and arc segments I can select, but spline segments start to develop random "offsets" in that I have to move the cursor off of the spline I want to select by a certain amount before the segment will highlight.  Sometimes I just have to draw a crossing window and deselect things that I don't want.

The other problem that occurs is that I'll get warnings in the tree saying that the sketch is over-defined or can't be solved, but when I edit the sketch, everything is blue or black and not a single relation is tagged as a possible offender.  Sometimes all it takes is "wiggling" a spline point a little bit and then Solidworks makes up it's mind that everything is okay after all.

Sometimes restarting Solidworks helps with the spline selection issue, but past a certain point in the development of the route sketch, it doesn't help anything.

Just wondering if anyone else is having these issues and if so, have you determined a cause and/or a workaround?