<p>I'm a bit lost here and I can't find much documentation.</p>

.NET workflows or ones created using SharePoint designer?
I've only got latter experience and they aren't really easy to debug, you really just have to do them 1 step at a time and test up to each step.
You can view the workflow state as well in SharePoint when you go to the List Settings (sorry I don't have a WSS machine to look at currently).