Hi Dave,
First of all I've no problem at all with you contacting me, I'm happy to help! I do have to be careful though as apart from anything else the process has changed recently so I'm not all that familiar with what people have to do these days!
What I can say fairly safely though is that safety and customer service are the big things they look for. With your answers, if there is a way to you can rope them into it it should help you. If theyve sent out any practice material for the tests then use it; chances are it won't be an exact recreation of the tests but if it gets your head thinking the right way it'll help! And don't be too nervous - the tests will be far from impossible. The role play I assume is you having to deal with a potentially difficult situation, although I'm not sure what ones they use. Again, I'd advise to be calm and relaxed, and do the thing that is the safest and\or shows great customer service.