OK uninstalled everything, reinstalled RTW, installed BI tried to start, said failed to initialise 3d audio. Checked and RTW and BI are installed in Program files not Program filesx86 so I copied the miles folder from Program files to Program filesx86 and this time BI started, screen came up but then closed immediately.

Have not tried installing patch yet since there is clearly an issue with BI 1.4. Must be something to do with normal program files or x86...?