Update: March 2017 - for information on upcoming changes to CricHQ/TCS and Play Cricket integration please view our FAQs here.
Go to the match menu, Play-cricket section.
First download the match. On this dialog you can search for the fixture and these settings will remain next time you download the game. At the bottom of the fixture list is a drop down allowing you to select players selected or registered league players. You can either begin scoring immediately or save the file for later.
If you start scoring, you are then presented with the new match wizard which will fill in the selected players etc.
If you have saved the file, you will need to go to the Play-cricket section and select import the fixture, when you begin scoring.
V6 now allows you to get the fixture and immediately pause the match.
Once the match is completed you can upload to play-cricket using the upload option. You will be warned if players are new to play cricket, these may be set to unsure on the play-cricket site, so it is worth looking there once you have uploaded.