The reply from tax advisor seems dubious to me. You can certainly use the company bank account to pay for anything you like, but if it's not an expense related to the company it will be considered drawings when compiling your accounts.
Also, as I understand it simply using your home to work from won't mean you are liable to CGT when you sell. If, on the other hand, you converted your attic for use as an office or added an outside office and claimed it back as a business expense, you would be liable for CGT. Open to correction though.....