The close trade screen is where you can manually close your trade.
If no target has been fulfilled, you will have only 1 option to choose from:
This option will close all of the trade orders and you will see no change in your portfolio.
If you want to close a trade that has already filled at least one entry point, you will have 3 options to choose from:
Close Trade (market sell all coins):
This option will close all of the trade orders and will sell the trade's current open position back into the base currency you bought with.
Close Trade (keep coins in the wallet)
This option will close all of the trade orders and will keep the coins (or position).
Close Trade (Activate trailing on remaining coins)
This option will cancel all of the open orders on the trade, the original trade will be closed and a new trade will be created with a trailing sell orders with of chosen percentage. When the trailing sell hits, the coin will be sold back into the base currency.