Couple of things I'd do.
First, relax, you don't need to know what the tool does.
If ur fixing a problem, then u just need to learn how to use Shift+ F8. Run the code till u see the problem. Stop the debugger and step one less until u get to where ur problem is upstream. At some point ur going to understand how it's all put together.
If they want you to add functionality, then create the forms, queries, reports n code you need to get the job done. And, a button/menu where it is initiated. Later on when u get familiar with the layout you may find that u have duplicated something. U can make different decisions then.
