When I use the built-in roadnav facility for downloading tiger/line maps, roadnav pops up a window listing every county in every state.
Scrolling back and forth in this window using the scrollbar on the bottom is very, very slow. When I click the left or right arrow in the scrollbar, my computer takes perhaps an entire second to update the display. This makes it very difficult to navigate the list of counties to select the ones that I want.
Also, when I click the OK button after selecting a county or several counties, roadnav produces a new window with a progress bar while it is downloading.
Roadnav uses 99% CPU time while this progress bar is displayed, even when roadnav isn't in the process of building maps.