As a supplement to the example program I posted earlier, I've put together this PDF guide. It explains how the program operates, and goes into some light detail about CanOpen itself, as implemented in Unitronics. Hopefully, it will help give the new CanOpen-er a boost in the right direction.
Like everything in this blog, this is open. If you see a correction or think something needs covered that isn't, let me know and I'll add on to it.
Hope it helps!