I ran across something called P2 touchpoints, what are those? Can they be used to run an external script? At what point in the startup process of Eclipse are they run?
Touchpoint is the actions could be executed in different phase when provisioning(install, update and uninstall) the features/plug-ins. There are some built-in touchpoint actions, such as setting program arguments, vm arguments and so on. P2 is a flexible system, you certainly can contribute your touchpoint action to do anything.