You need to make the pages called "GroupMemberXButtons" (with X=1 to 6) wider so the buttons fit in.
And just to explain why I don't add more buttons even though there appears to be the space for it: On the group window (regardless of the variant) there is actually only space for one more button (of course you can enlarge it further if you want). However, on the raid window all available space has been filled and I don't want to make it even larger than it already is. So that's why there are 5 buttons.
