Adding an extra "R" in the last name?

The reason why I changed my last name by adding an extra “R” (next to an existing R)? If I say I was motivated by numerology, would they later ask me if someone could blackmail me?

Also, my nickname was shortened - pdf form does not have a space for nickname - will the online form has space? In addressing the nickname, should I repeat my first and lastname?

You are probably not going to be asked if you could be blackmailed because your name-change motivation was numerology. But if you think someone could use this to blackmail you, then you should report it if you have an interview.

If there isn’t room to list the entire nickname, list it in the optional comment with an explanation. I think the system requires you to list the middle/last name that you use with your nickname. Either way, I would include them.