No you don’t require to install outlook on your machine for conversion but if you choose PST format for saving MSG data, then you require installing outlook on your machine.
Yes, during conversion time you can choose “Messages skip between dates” through which you can define two dates “from date” to “to date” to recover only selected emails along with attachments.
Well, this kind of situation you will never face because our team always presents to give a feedback to our users and if in case anybody don’t get any information about their product, then they can instantly contact with our support team by this email address support@enstella.com having complete details regarding your product.