The styleheet file he sent you was for UBB.threadsâ„¢ 7.4.1p2
Which is really old.
If you are using a newer version.
Then you will need to preview the style after importing and fix several additional new settings that are with the newer version in the style editor.
Now most of them will probably have a copy feature for the new settings.
And they will work most of the time.
