My problem is exactly the same..
I unbranded from Vodafone to generic using these files:
K770_R8BC004_FS_MEDITERR_RED53.fbn
K770_R8BC004_MAIN_GENERIC_VI_RED53.mbn
HB1-06_Gen_CDA102568_4_R8A_GENERIC_MEDITERR

all of which i downloaded from here...
The process went fine, the phone is fully debranded (and faster I may add) but I have 2 issues:
I cannot assign a shortcut to the up button, as it is greyed out in the menu saying "Cannot set as shortcut" when i press it. It is defaulted to the photo viewer

Plus the answer and end call buttons do not work as expected..
the answer button opens up the web browser and the end call button opens up the shortcuts pop up menu...

What can I do? Rebranding is not really an option as i hate the vodafone stuff.. can i edit some file in the tpa folder or something like that so i can change these?