Running:
root@transmission_1:/ # /usr/pbi/transmission-amd64/control.py start 192.168.NNN.MMM PPPPP
/usr/pbi/transmission-amd64/control.py: import: not found
/usr/pbi/transmission-amd64/control.py: import: not found
/usr/pbi/transmission-amd64/control.py: import: not found
/usr/pbi/transmission-amd64/control.py: import: not found
from: can't read /var/mail/flup.server.fcgi
/usr/pbi/transmission-amd64/control.py: 8: Syntax error: "(" unexpected
root@transmission_1:/ #
(Where N, M, and P are anonymized) suggests that some important parts of Transmission are missing.