> if i decide to "cut the limit" going to the option again 
> and in speed limit put "none" (really there isn´t "none", 
> but a "blank" space) the program continua limiting to the 
> speed selected  before..

Yes, because the GUI only detects options that changed AND 
not empty (empty == "default settings", which has a 
different meaning during the mirror)

By the way, using the maximum speed can be *really 
dangerous*, and should *NOT* be used except in rare cases 
(load tests/stress tests), as domestic lines tend to be 
faster than server lines (it is not rare to see 20MB lines 
for domestic use nowadays, and many servers do not have 
such bandwidth for all their users)