Thanks, I couldn't find any method for it, but the help section says this:
The RME Multichannel WAV File Batch Processor offers the easiest way to combine and split those multichannel interleaved files into single or dual channel files. The content of consecutive files is automatically combined into a single file. In the rare case that these again exceed the 2 GByte limit the tool automatically writes RF64 files. The Mac version can also write CAF (Core Audio Format) files.
Hence my confusion.
