Hello:
This will fix your issue--In FSX, you will see a setting that says "advanced animations." If this is not checked, you will not see the flaps or spoilers deploy. I know, because when I had to reinstall FSX, I forgot to check this setting.
In settings, click on the "graphics" tab. In the Global Options section on the right-hand side, you will see the settings for "advanced animations." Click in the check box to activate.
Hope this helps.
Robert