Remember after the meeting you can appeal against what ever they give you, warning, written warning etc, and that appeal is placed above the level that the person interviewing you.
This is where you really make your appeal for the whole process, these nasty managers can make it very hard for you to get your side across in these meetings, so this appeal letter is where you roger these "little hitlers", killer blow is them swearing, being thretening, state how you should look up to managers but feel you cannot in this case, etc etc etc. Write a knock out appeal letter and your sorted.
I would not accept any type of warning if unwarrented.
You get 7days i think to appeal against what they give you, was for me anyway. Before you write your letter request all data they hold on you regarding the case, this inlcudes all their notes they took during the meeting.
GL