When viewing the My Modules tab in the module browser I expect to see at the top of the list the module I added most recently. The order follows some other rule though. Maybe it is sorted by date it was added to the site? Wondering...

It follows the same rules like a standard search. So you can sort by Newest, Popular, Alphabetic, Price, HP, Manufacturer, Depth.
All the other search parameter work, too. So you can filter for VCA or manufacturer.

Alright to all of that.
It just expected to see my latest module on top of that list. In fact it is not.
Instead, they are sorted by some other date, probably when the module was first entered into the data base.
Am I more clear now?

I just purchased Unicorn to have my collection there but it seems only one module from my collection is visible there?

Pretty sucky to flesh out €20 for one function that doesn't work. Is the fault on my end?

You can search in your collection like in the ModularGrid database. If you reset the search form, you should see all modules you have added.
You can also add all modules in a rack automatically with the Edit-> Add all to my modules drop down.

Works fine now had some wierd search setting limiting my view. Thanks!