Where are functions called?

So I just downloaded and installed the imce and imce_gallery modules and they seem to be working fine except for one problem. One of the functions requires an array as input but it is recieving a regular integer variable. I've looked through my files and through the forums but I cannot seem to find anything that helps as of yet. What I would like to know is where the functions for a module are actually called. It seems that the variable being put into this function is not set properly so I would like to find the file that calls the function to see how the variable is being set. The function is defined in the .module file, but not called there. Does anyone have any clue where (or in what file) module functions are called? Thanks for your help.