1. the solution to that line is in your defined system colours, its part of the system colours, change the colour of either of these one by one to a psycho colour like fluro green or pink (something that your gonna see when you change it)
button highlight, button shadow, buttondrkshadow,buttonlight. imsorry i gave you a bit of a list, but i never remember which one it is, until im actually working in that section. this will solve that problem, but also be aware that changing these colour could affect your disabled font settings in drop down menus.........so you have to choose your colours wisely.
2. the second prob is easier, just change your menu item to png, not bmp and remove the pink and check transparent parts and alpha channel parts on the image in skinstudio and you should be fine.