When emitting or updating a Particle System from a Population Tool Locator, connections between the new Particle System and the Population Tool Locator are automatically created.
However if you want to add or modify the process of these connections, you can overwrite the following function:
glmParticleHandleConnections(string $particleSystem, string $popToolNode)
This function is located in glmPopulationToolUtils.mel file in the Golaem scripts directory.