Okay, if you finished everything above, make sure the game is not open, if it is, close it and click on "Load" button. Inside the folder, there will be another folder called "assets", enter it; Ok, ...
If you want to see some research made on files (GLADIATO.UBR, SPRITES.UBR, INGAME.UBR, DD4FRONT.UBR), put the imhex_dda_project.hexproj file in the root folder where the game assets files are. And ...