[chirp_users] Radio disabled

Hi, I am trying to program a Baofeng UV-5R. I have uploaded a data sheet from the radio, imported 3 repeater stations from the repeater book and then uploaded to the radio. Now the radio will not allow the a/b switch, the menu switch and the vfo/mr switch to work and will not transmit the offset freq, Also (assuming that I can get the radio to work again) how do I import additional stations to the radio without overwriting the ones already there?

Thanks for any help available