EZY,
Please do not be concerned. Your individual scores do not count towards BA's final decision if you make it through to the final stage. I applied for the BA FPP in 2012 and in 2013. In 2012 I scored 60% in the verbal reasoning and 67% in 2013. Each time I progressed to the final stage. Would you really want to to retake the verbal reasoning test and risk scoring less than 60% which would rule you out the final stage already?
Believe me, you should be delighted that you don't have to retake the written tests. Nail the interview and thr group exercise and you will make it to the final stages.
Also, if you make it through to the final stages then all you need to do is pass each stage of BA's assessment and you'll be successful. It is a new playing field and previous scores at FTO's are not taken into consideration.