1) go to miui settings (available in the menu) and turn on and off battery indicator.Indicator style can be chosen in the standard settings under battery submenu

2) look one page back...

I have another question - how to get QWERTZ keyboard layout? The MIUI way does not work.
EDIT: changing layout via magicbox do not work
my quick comparsion of ROM speed (smoothness)
(from fastest to slowest; bold one is the ROM I'm currently using)
  1. MS2Ginger 5 (-Danik-) / CM7 (tezet)
  2. Stock Gingerbread ROM (UK SBF)
  3. MIUI (will5)
  4. CM10 (tezet)
  5. Stock Froyo ROM (UK SBF)