I eventually found the time today (after nearly a year) to upload my TMSnake game for RC2014 systems to RC-BOX BBS (the world's first -and currently only- RC2014 based BBS).
Up/downloads are possible on the CP/M command line using the KMD transfer command.
NOTE: only old (8 bit CRC) xmodem and ymodem protocols are supported.
Transfers tested with QTERM on CP/M as well as CCGMS Future and StrikeTerm on a Commodore 64.