This is a command line program I wrote to take a full image and cut it into diagonal 44x44 sized tiles so you can import it into your art file.
More information and screenshots are on the github page -> GitHub - bittiez/UO-Iso-Tile-Slicer: A program to slice an image into tiles for use in UO statics
More information and screenshots are on the github page -> GitHub - bittiez/UO-Iso-Tile-Slicer: A program to slice an image into tiles for use in UO statics