The problem is, that Mp3tag looks for the first blank after matching %album% and treats this as seperator.
You can rename your files to have a proper seperator like - between %album% and %track% using this action:
Action #1:
Action type: Replace with regular expressions
Field: _FILENAME
Regular expression: (.) - (.) (\d*) - (.*)
Replace matches with: $1 - $2 - $3 - $4
Hope that helps.
Best regards,
~ Florian