When processing inventory (ie. goods receipt and goods issue) and production documents (ie. receipt from production and issue for production) you can use these shortcuts:

Function Menu Command Shortcut key
Display details of the selected row Goto > Row Details Ctrl + L
Move to the first row in the table Goto > First Row Ctrl + H
Move to the last row in the table Goto > Last Row Ctrl + E
Proceed to the Remarks field Goto > Remarks Ctrl + R
Show item serial numbers Goto > Payment Means
Ctrl + Y
Show item serial numbers Goto > Transaction Journal
Ctrl + J
Show item serial numbers Goto > Business Partner Code
Ctrl + U
Show item serial numbers Goto > Batch/Serial Numbers Ctrl + Tab in the Qty field
Copy the amount due to the Total or Amount fields in the Payment Means window Right Click > Copy Balance Due
Ctrl + B in the Total or Amount Field
Move to the next active field after you have changed the business partner name or G/L account name in Checks for Payment Ctrl + Shift + Tab