The plot thickens, strange !
The "further diagnostics" bit of the BT WS Performance Checker has always been a bit temperamental with me, rarely worked on the first attempt, same goes for the "mouselike.org" BRAS checker, as they are both accessing the same BT system to obtain the BRAS IP profile perhaps to be expected.
Neither have completely refused to work at all as per the experiences of the last few days.