Problem with new feature in Function App

[Brad Barton]

There appears to be a bug affecting the new Transform function when combined with the Tangent function in the Function Plot App. If you first implement Tangent, then use Transform to move the graph to a new location, returning to the Tangent function yields an obviously non-tangent line. It looks like the Tangent function doesn't update to the new location, showing a line with the a slope from the original location, but intersecting the graph in the new location.

To reproduce the error:
1. Enter a simple function in the Function App. --> F1(x) = x^2
2. Go to the plot screen and implement Menu/Fcn/Tangent
3. Press the right or left arrow a couple of times to show the tangent line
4. Implement Menu/Fcn/Transform and offset the graph in the X direction
5. Exit the Transform function by closing the bottom window with the down arrow softkey, or by returning to the Tangent function via menu.
6. Using the arrows, move the cursor left or right and note the incorrect tangent line.

The Slope function seems to be affected as well. It looks like the software needs to be modified to update the function's look up table when exiting the Transform function. The problem might be more complex than this because the Root and Extremum functions seem to work fine.