Bridge > Tools > Photoshop > Loading into Photoshop layers, is a script, so it will be possible to write a new script giving some control. If you just want to reverse the layer order, you can do that from the Layers menu after they open.
Layer > Arrange > Reverse
Wow! That was a fast reply Trevor. Thanks!
If anyone out there is interested in writing this script, to control the loading order of files as they are selected,
I am very interested in buying that! It would be hugely beneficial for loading various combinations of files on the fly.
There are several ace script writers here, but go ask on the Scripting forum
Be sure to give exact details of your requirements, along with the operating system, and Photoshop version you are using.