Emacs - Buffer List - Drop-Down-Menu

[Will]

Dear all,

if I press C-Mouse-1 the buffer list appears as a drop-down menu at the 
mouse-pointer. However, the justification seems to be messed up and I 
have problems orienting to find the buffer /folder names.

How can I change the justification of the buffer list so ist flushed 
left (like in Emacs menu -> Buffers)? How can I influence the sorting of 
buffer names in that list?

Thanks in advance,

Will