I have that same program and have had it since the beginning of it's creation and to this day, I've never had any problems with Freelancer, installing it or, whatnot. I also have several Freelancer installs for each mod I pay.
Whenever you do a fresh install and go online, Freelancer will always create a new MPIP, however, you just delete that one and add your original ID in return. I still have two of my first ever FLID's and have re-installed Freelancer on several PC's at least 100 times now and from server to server, those that don't do player wipes, all my characters have still been there. These ID's are 10 y/o.
Another thing I use is, the Freelancer Account Manager. I have used it for years because it too, creates an ID for all your characters/accounts, separate from the Freelancer ID. Once it does this and it creates a file, I locate the file that holds all the Signature/Codes it generates and put them in another file then, I save them to an External HDD or, Thumb-Drive. If something happens to my system, I can always replace them after I re-install everything. I also do this even when I have to change MPID's. Since they are coded differently than how Freelancer codes your game, they can be used on any Freelancer MP account you have created.
All that aside, always write down your FL-MPID and put it somewhere. Pencil & Paper are still of some use in this world and always will be. Not only do I write that/those ID's down, I also write all the Sig/Codes in the Freelancer Account Manager down, they can be manually added to the FLAM. I know it's time consuming but, if you want to save what you have, you can't always count on any PC to do it. Not only that, you can also take a screen shot of them then, print them out and put them somewhere.
That's not all, many Server Ops maintain backup files in case something happens to your installed game/account and they can replace your characters for you, no matter what MPID you have changed too.
Hope this helps?
: I still have all my players accounts from back when I run a Disco Server years ago, for 4 + years. If I were to put that server back online, I can add all those accounts, whether or not, the players remember all their characters names and they can continue from where they left off. If they create a new account, I can add those characters to that account as well. I don't see me running any Disco server anymore so, that's not happening.