After re-enabling LiteMage Cache, the site's header, footer, and other dynamically-loaded blocks disappear. Also, the Flush LiteMage Cache button under System > Cache Management in the Magento Admin Panel disappears.
Litespeed_Litemage output was mistakenly disabled
Log into Magento Admin Panel, go to System > Configuration > ADVANCED > Advanced > Disable Module Output, make sure Litespeed_Litemage output is enabled, then save config.
The correct way to disable the LiteMage module (not only output) is: System > Configuration > LITEMAGE CACHE > LiteMage Configuration, set Enable LiteMage Cache to No.