As the ticalc.org page says: » Shell-Developers Development of assembly shells for any of the TI graphing calculators. This list is only for developers - no usage questions, please. This mailing list isn't for usage questions. I have a TI-89 and HW1 and 2.03 and I install DoorsOS and I don't have a problem as long as I don't use the Doors Explorer. Did you download hw2patch?