1.  In my opinion I would have to say that Jean-Baptiste Lamarck had a positive influence over Darwin mainly because they both agreed on the basis that life gradually changed over time and continued to change, living things continued to increase their chances of survival through adaptation, and they both believed that life came from simpler organisms thus turning to complex organisms.

2.  In 1801 Lamarck began to publish his detail on the evolutionary theories.  He is known for his Theory of Inheritance of Acquired Characteristics which practically says that living things adapt to their environment thus passing it down to their future generations. (http://www.ucmp.berkeley.edu/history/lamarck.html)

3.  The bullet point "In order for traits to evolve and change, they MUST be heritable" affects Lamarck's work because in his work he uses examples such as elephants previously having short trunks, but after time they adapted to have have longer trunks and of course that was through a long process of generations and generations of adaptation.

4.  Darwin could have developed his ideas without Lamarck just because there were plenty of other people who had the same idea or were on the same path.

5.  The attitude of the church toward Darwin's book On the Origin of Species actually angered the church and the old Natural theologians responded very negatively toward it.