The Lederer scoring is interesting. It’s similar to that used in the Pachabo event held in England and the qualifiers for same.
Matches are scored using a combination of IMPS and Point a Board methods. The results are separately converted into Victory Points (VPs).
Every board gets scored along the usual IMPS scale used for teams. All the IMPs are added up. Some of the VPs are allocated for the number of IMPS a team wins by (15/15 for a draw up to 30/0 for a win of 45+ IMPs over 9 boards).
Then every board is scored again using an alternative method called Point a Board. The rest of the VPs are allocated using these scores. For each board a team gets 1 VP for a draw and 2 VPs for a win (18 in total for 9 boards).
Thus there are a total of 48 VPs for a match – 30 from the IMPs scoring and 18 from the Point a Board – to be shared between the two teams.
So players need to bid and make their games and be mindful of overtricks and undertricks. Very fiendish.
The PDF here gives more detail: 2015 Display – Scoring