BoosteR, if you only want to set the first letter of a sentence capitalized, you could use:

on *:input:*:{
  if ($left($1,1) !isin / $readini($mircini,text,commandchar)) && (!$ctrlenter) && (!$inpaste) {
    say $regsubex($1-,/^(.)/,$upper(\t))
    halt
  }
}