Should this be registered as a bug on sane-backends?

As neither simple-scan nor xsane works, this page (https://help.ubuntu.com/community/SimpleScanHardwareIssues) suggested to register bug on sane-backends. Not sure, so I'll just ask a question for now.
Please let me know if I should register this as a bug on sane-backends.

Setup:
Printer: Canon MG6650 wlan connection
Ubuntu: 15.10
libsane: 1.0.25+git20150528-1ubuntu2
xsane: 0.998-6ubuntu1
simple-scan: 3.18.1-0ubuntu1

Downloaded and installed printer and scanner deb-packages from Canon. Printer works, and the supplied scangearmp2 sw works. Software is limited, so I wanted to get simple-scan working.

Starting xsane, it goes straight to a "scanningfor devices" box, shortly followed by a new window saying "Failed to open device 'pixma:MG6600_192.168.1.20':Invalid argument.

simple-scan finds the printer name as given by the printer (as Bonjour service name).
Trying to scan gives "Failed to scan" + "Unable to connect to scanner" with buttons "Close" and "Change Scanner" in a red banner at the top.

Debug option for simple-scan gives:
[+0,00s] DEBUG: simple-scan.vala:674: Starting Simple Scan 3.18.1, PID=18004
[+0,00s] DEBUG: Connecting to session manager
[+0,04s] DEBUG: ui.vala:2018: Loading state from /home/xxxxx/.cache/simple-scan/state
[+0,04s] DEBUG: ui.vala:1986: Restoring window to 600x400 pixels
[+0,04s] DEBUG: autosave-manager.vala:64: Loading autosave information
[+0,04s] DEBUG: autosave-manager.vala:259: Waiting to autosave...
[+0,04s] CRITICAL: gtk_event_controller_reset: assertion 'GTK_IS_EVENT_CONTROLLER (controller)' failed
[+0,08s] DEBUG: scanner.vala:1446: sane_init () -> SANE_STATUS_GOOD
[+0,08s] DEBUG: scanner.vala:1452: SANE version 1.0.25
[+0,08s] DEBUG: scanner.vala:1513: Requesting redetection of scan devices
[+0,08s] DEBUG: scanner.vala:802: Processing request
[+0,14s] DEBUG: autosave-manager.vala:281: Autosaving book information
[+0,19s] DEBUG: ui.vala:2109: Saving state to /home/xxxxx/.cache/simple-scan/state
[+3,44s] DEBUG: simple-scan.vala:404: Requesting scan at 300 dpi from device '(null)'
[+3,44s] DEBUG: scanner.vala:1559: Scanner.scan ("(null)", dpi=300, scan_mode=ScanMode.COLOR, depth=8, type=ScanType.SINGLE, paper_width=2100, paper_height=2970, brightness=0, contrast=0)
[+4,17s] DEBUG: scanner.vala:338: sane_get_devices () -> SANE_STATUS_GOOD
[+4,17s] DEBUG: scanner.vala:350: Device: name="pixma:MG6600_192.168.1.20" vendor="CANON" model="Canon PIXMA MG6600 Series" type="multi-function peripheral"
[+4,17s] DEBUG: scanner.vala:802: Processing request
[+5,05s] DEBUG: scanner.vala:863: sane_open ("pixma:MG6600_192.168.1.20") -> SANE_STATUS_INVAL
[+5,05s] WARNING: scanner.vala:867: Unable to get open device: Invalid argument
[+5,15s] DEBUG: ui.vala:2109: Saving state to /home/xxxxx/.cache/simple-scan/state
[+10,40s] DEBUG: autosave-manager.vala:195: Deleting autosave records
[+10,40s] DEBUG: scanner.vala:1586: Stopping scan thread
[+10,40s] DEBUG: scanner.vala:802: Processing request
[+10,41s] DEBUG: scanner.vala:1597: sane_exit ()