Multibit was abandoned by its developer quite some time ago so it is no longer maintained. You should move to electrum wallet. You can import your private keys from multibit into electrum direct so there is no need for a new address or wallet file transfer.
Great suggestion. I'll try that now.
I have answered here:
https://bitcointalk.org/index.php?topic=1841089.msg19071417#msg19071417Thanks a lot!