There are a number of Speed Keys and shortcuts to help you do things quickly in League Manager:

To quickly find a player, start typing their last name while viewing a view that included player names.

Speed Keys:

F1  - Brings up Help System
F2  - Recalculate handicaps and point totals is
F7  - Inactivate an active player or Activate an inactive player
F8  - To mark a player in skins, highlight the player and press F8
F10 - Immediately calculates the card.  Cards are automatically calculated when you type the last score or exit the card, so pressing F10 is not necessary.

+  - Brings up the scorecard; closes the open scorecard.

TAB - Moves the cursor to the next box in a form

CTRL+E - Exit League Manager