Under recent versions of OS X, the track sheet has been causing long delays when switching to and from its window. This is due to some underlying system behavior that takes a while to update a large table when switching windows. There does not immediately seem to be a way of preventing the system from doing this.
So, the latest build, 3.9.6 (9301.1) adds a workaround solution. The new design minimizes the delay caused by the operating system by limiting the width of the Track Sheet table to only the number of columns that will fit into the window. Buttons are added to page left and right through the channels.
For a window width of 20 channels and around 150 cues, the delay when switching to and from the Track Sheet is only around 2 seconds. This is much less than the 10 or so seconds of delay when the Track Sheet displayed a table with all 200+ channels.
Perhaps Apple will eventually address this issue. But, using the newer view based table (as opposed to LXConsole's use of the original cell based tables) actually seems to make the delay slightly longer. View based tables have been included in OS X for a while. But this particular issue seems to have started with Yosemite. LXConsole running on OS X 10.8.5 with a large track sheet exhibits no delay switching between windows.