Sibelius Update Always Crashes!

I Installed and registered Sibelius 5. Then I downloaded the update to 5.2.5 that was recommended. I installed that and registered that. Mind you, the Sibelius Icon didn't look right - (It's the mac one with the pencils making an 'A'). Anyway it all starts hopeful (after re-registering like it said) then crashes every time.

I took one guys advice and took out vst and audio plugins from their folder, but no change.

I tried installing both versions plenty times too.

I have a PowerBook G4 with a gig of RAM - more than enough.

Any help/solutions would be greatly appreciated.

Try to go back to 5.2. Then update Sibelius again and see if it works - I didn't have your problem.

You are using OS X.4.9 or later as the specs demand?

Computer requirements for Sibelius

Sibelius Still crashing

Cheers for the replies - yeh, using leopard 10.5.6.
Will give the 5.2 thing a try...