Sorting Data from Highest to Lowest

Data Table on Sheet 1:

Relevant data range between D:L; Cells are from 5-2000 only

Blank Table on Sheet 2:

Pre-made data tracker I am trying to figure out

- Essentially, I am trying to filling the table in Sheet 2 only using formula's

What I am trying to achieve (from left to right based on Blank Table in Sheet 2):

- For the Supplier and Total VPs columns, I want to have the sum of VP codes (there are multiple codes and I want the sum of any of these codes per supplier) used for each specific Supplier in Sheet 1; BUT only capturing the top 15 from highest to lowest

- For the 1, 2 and 3 columns, I want to have the top 3 codes used for that supplier and if only one code is used, only the top spot will be filled

- For the Main Issue column, I want this to be the highest occurrence issue which is pre-filled when entering codes and this data will be in the VP description section of the data table in Sheet 1

I apologise if my clarification is unclear and am happy to elaborate!

Thank you