Hi Jim, don't go into the pre-planning meeting expecting 'success'! Trying to avoid failure is more like it!
The first thing the planner will probably say to you is that nothing they say in this meeting will constitute an indication of approval for your application!
We had two meetings, the first said that our design was great and that we would have no trouble getting planning. Our planning was refused. The second, a year and a half later, with an unchanged plan, said that we would have no chance of getting planning. Our planning was approved!
The whole process is a mess - particularly here in Offaly - if you are lucky and there is some consistency in your local planning department, you may escape with your sanity!
In the end, it was the local need that got us planning (two parents to look after, one with cancer, one with Parkinsons) and even then it took two and a half years!