ROS Explorer floating (sub)menu's errors (tear-offs)

There are some errors with the floating menu's which are related, so i'll just
enumerate them here:

first:
they stay on sometimes. This sequence let one stay without properly 'detaching'
it from the startmenu:

start-settings-adminitstration
now move the mouse in a straight line to the left.

The most right submenu stays (CORE-1), floating, now there's a taskbar button,
but there's no rightmouse menu on it. Thus i cannot close this 'application'
using the taskbar (CORE-2).

now i click on the blockythingy in the rigth upper corner. It becomes a real
window now, but the taskbar button disappears (CORE-3?).

At least all behaviour is strange, i'd need to check for correct behaviour in
win98 though, which i will do later