the ipk is trying to overwrite files that already exist, this is why its not installing. i have just tried it on a fresh PLi flash
Installing enigma2-skin-sky.new (Chababu.V2.3) to root... Collected errors: * check_data_file_clashes: Package enigma2-skin-sky.new wants to install file /usr/lib/enigma2/python/Components/Converter/EventName.pyo But that file is already provided by package * enigma2 * check_data_file_clashes: Package enigma2-skin-sky.new wants to install file /usr/lib/enigma2/python/Components/Renderer/CoolNextEvent.pyo But that file is already provided by package * enigma2 * check_data_file_clashes: Package enigma2-skin-sky.new wants to install file /usr/lib/enigma2/python/Components/Renderer/CoolPico.pyo But that file is already provided by package * enigma2 * opkg_install_cmd: Cannot install package enigma2-skin-sky.new.