What I found was that after installing Flashlite 3.1 opera mobile plugin settings did not update to the appropriate registry key.
I found that the plugin config for opera is under the folder Application Data/opera9XXX and the file is axobjects.ini
Copy this file to your desktop and modify the CLSID registry key under [Shockwave Flash] to match the registry key for flashlite 3.1
This key can be found by using a .CAB editor like WinCE or by searching the registry \HKCR\ShockwaveFlash.ShockwaveFlash\CLSID
**This does not work with the current beta available on opera.com but works with pre-installed versions.**
I hope this is of some help to people!