From Mental Health Law Online
The donor executed an instrument intended to be a personal welfare LPA. It contained the following defects: (i) the certificate provider had failed to tick the first two mandatory boxes in Part B, (ii) the attorney had failed to tick any of the boxes in Part C, although he had dated and executed it, and (iii) the replacement attorney had ticked the appropriate boxes in his Part C but had not dated or executed it. The Public Guardian refused to register the instrument, and the donor subsequently lost capacity. On the attorney's application, the court directed the Public Guardian not to register the instrument, because "the errors in its execution are too fundamental".
The summary above is taken directly from the OPG website. The case is listed as "Re Murdoch (an order of the Senior Judge made on 30 October 2009)" under the heading "Whether the instrument is in prescribed form - unticked boxes".
Not on Bailii.