these idiots stopped service (without notification) on 26th july and in this moment just one peer connected, so no sync and no chance to import their useless master seeds anywhere
You create a new wallet, select I already have seed, when you type seed you need to click the "options" button and select BIP39 seed. It will ask for a derivation path... you need to use: m/0' (note the ' it is important... m/0')
That should show all your MultiBitHD addresses and history.
To get BCC, you'll need ElectronCash (www.electroncash.org) v2.9.0 it also supports this feature as it is a fork of Electrum modified to work with BCC. Suggest you do research as there are some issues with it not connecting to BCC chain sometimes. http://reddit.com/r/btc/comments/6qyn18/electroncash_notice_how_to_select_bitcoincash/