Add punctuation: An investigation Rambll Management 2001 has estimated that ca 163000 people work as independent entrepreneurs in Denmark and that they represent a growth area
A: An investigation (Rambøll Management 2001) has estimated that ca 163,000 people work as independent entrepreneurs in Denmark, and that they represent a growth area.

Add punctuation: When its deleted by Comodo Internet Security Pro 2012 the infected DLL file would be removed too
A: When it's deleted by Comodo Internet Security Pro 2012, the infected DLL file would be removed too.

Add punctuation: The Fiera Milano City exhibition center is just a short distance away as is the Duomo the Church of Santa Maria delle Grazie and much more
A:
The Fiera Milano City exhibition center is just a short distance away, as is the Duomo, the Church of Santa Maria delle Grazie, and much more.