Help with pseudocode for design document?

I have no idea what your requirements or goals are for this project, and therefore, I can't really see any way to help you. Honestly, pseudocode is not that hard. There's not much of a solid format to it, you're just trying to lay out your general strategy for dividing and conquering your tasks. It's actually easier than regular source code, because you're basically just marking out a bunch of placeholders for real code.

For example, if I was trying to do a File dialog, I might do something like this:

filepath = openFileDialog();

if (!filepath) {reportError();} else {doThingWithFile();}

Obviously this is going to be expanded out later, function names will change, functions that are referenced will actually be written, yadda yadda yadda. But I've added a layer of planning to it, which is essential in larger programs, whether it's accomplished with pseudocode, diagrams, hand gestures, or any wild and crazy combination of the three.

Sounds like you are writing this to be handed off to someone else for development. I'd suggest you use a Use Case rather than pseudocode. This will get you much better results... it's like going into a mechanic's shop and telling them what you want the outcome to be rather than outlining the steps you want them to take to fix it.