Liudr,
I uploaded the phi_panel_backpack_20X4_1_6_4(rotary+5keys).hex firmware with no problem.
I wired up a rotary encoder according to your Phi-panel backpack assembly and keypad options 20130101.pdf
Table 3.1 Rotary encoder keypad connections V1.0
Can you provide an example sketch that uses this configuration?
Thank You,
Igor27