Pitch Modulation on Note

That depends on what you mean by "at the end" - is it after a fixed amount of time or upon a note off (releasing the key)? In both cases you modulate pitch with a "descending" source and then compensate for the increase in pitch at the start of the note by lowering the pitch using the semitone knob, and if the modulation is not semitone accurate you can also correct the pitch by a small amount using the constant sources in the modulation matrix.
In the case of a fixed amount of time I'd use a sawtooth LFO in ENV mode with its contour bent up to become flat with a sudden drop at the end. The amount of time can be controlled by the LFO's rate. In the case of the note off response I'd use an envelope with no attack or decay, just sustain at full amplitude and then a decay tail. In this case you also have to remember that the amplitude envelope has to have a decay tail as well for you to hear the pitch drop. And this is an opportunity to reiterate a feature request: if Access could implement an option to make the LFO-s and envelopes triggered by a note off as an alternative to a note on, it would eliminate the necessity to compensate for the pitch.
Good luck!