If you are trying to convert older .br6 files from Bryce to the later .br7 file format, you will need to download the latest version of the program from internet (it is available for free now) and re-save it using the default program functions.
There really is no other option how to perform br6 to br7 conversion, just keep in mind you will no longer be able to downgrade the version of your file, so always keep the original backup.
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