The lines don't show up when a resource is in range.  They show up when an unclaimed resource is in range.  Has another race already claimed those resources?  Your constructor doesn't have enought sensor range to see a starbase or two that may have already claimed them.  The way to be sure is to put your cursor on the resources and see if a tool tip appears that a starbase has claimed them.  You should do this before sending a constructor there.

I started a new game and changed the color scheme and there is now a circle around the constructor showing its range and the moving dashed lines showing the resources that are in range.  This suggests to me that you might want to add some logic that works with the color scheme(s) selected by the player to ensure that everything will be visible (no 2 objects that could overlap have the same color).