I am trying to use this BL to customize tree display for VPMReference for specific user or for specific attribute on VPMReference in Product Finder Classic, System Finder, or Manufacturing Finder.

Here is sample code:

let EXT(XP_VPMReference_Ext)
if (EXT.Node =="ABC")
{
    Parameters->SetAttributeString("IconMask","I_TP")
}

Its not working.

Question:
Where to keep the image files?
What is missing to make code working.