Hi here is the lib you could use to create a GUI tristate treeview. Just take a look in the zip-file. Extract all files in to the same dir and the take a look into the sample-file. I also put some state image bitmaps in. It's just like a beginning (version 0.2). The next thing I'm working on is to check for the right state: that means it's not usefull to put the state "GUI_INDERMINATE" manually to an item! And if the state of an item is changing then call a userdefined function to i