I am running a laptop with Windows XP. I have had this problem on both Internet Explorer and Google Chrome.
My game "Barakus by Samuel" has myself (with custom picture), and 3 players. 2 players have the image issued when they signed up. One has a custom image. The two with issued images I can hover mouse over their icons and get the options "Dismiss Player, Promote to GM". The one with the custom picture, the same option will pop up, but there is a gap between his picture and the options. If I move the mouse OFF his picture, the options go away.
As a suggestion, since I can access a small bio of the players, perhaps there should be an option to dismiss the player from my campaign from there.
I feel bad complaining at all. I really appreciate what this site has done for me.