Fix invisible cursor?
If your mouse cursor has mysteriously disappeared in OS X, try the following tricks in descending order to bring it back:


Hit Command+Tab to switch back to the Finder or to another app, then switch back to the active app
Summon the Force Quit menu by hitting Command+Option+Escape, there is often no need to actually force quit anything as just summoning the menu is often enough to make the cursor return
Quit and relaunch the app, or quit all apps if the cursor is gone everywhere
Adjust the size of the cursor, found in System Preferences > Accessibility > Display to make it reappear


Reboot

Let me know if problem remains.