Just as a quick update I've taken a look into the Hud Plugin you're using and found a way to make it work but I'm trying out other ideas to find what works best. Currently I have it changing the icon that shows in the Item box on the HUD but I'm not 100% satisfied with this method until I try some others as well. I'll post with an update some time soon for this so far it's been rather simple to add in.
The HUD that is used in the youtube video for this plugin which shows the effect you're looking for was actually made using SumRndmDde's HUD Maker to display the images.