Connect the inverter to the grid via a fuse. Install the CT correctly on that LIVE input wire. Turn off (If you want to) the grid by turning off the fuse. When you need the grid, just turn on the fuse.
No need to bond anything unless you have special conditions/regulations in your country that...
But again...WHY?
As Steve mentions the power use is MINIMAL.
And if you consider a BT module as a security risk with its max 5-10m range...well, there are other stuff to worry about.
Running only the Chargeverter to maintain your batteries and not connecting the inverter to the grid gives you much cleaner power if your grid has noise.
I do this here due to a noisy grid.
See the link to my battery build thread in my signature.
Did you remember the B+ cable (I think thats what its called in the manual) also to the last cell (16) and not just the sensor? That one is the last on the number 2 connector (the long one).
Your climate is something like England so I figure producing much solar will be an uphill battle, yes?
Especially companies would like their power to be up and running every day.
As mentioned above ^^ ask a local sparkie for rules and regs in your local market for resellers.
Not much. Here the dust is around max. 5-10% less production.
I let the local rain flush mine off, ca. 30 degrees roof mounted.
If you have big amounts of calc in your water, do not use a hose.
There will be calcium spots when they dry.
Aka better with natural rain - no calc.