Basically, with a good SD card, you can write about 20MB/s on the Pi/BBB. However, the 100Mb connection only allows transfers of about 8MB/s (and actually significantly less than that as the FTP implementation in wxWidgets sucks). By compressing (gzip) the fseq files (which are in general very highly compressible, 15:1 or higher is not unheard of) we can transfer the files MUCH faster and then uncompress them at the full 20MB/s. This was added in .45. I can now transfer my entire show in about 10 minutes compared to over 30 minutes before. So with .45, it does compress the fseq to a gzip file in memory first, transfers the file via the same HTTP "upload" that would occur if you use the FPP web page upload, and the update to FPP's "post upload" scripts detect the gz and uncompresses it.