On Ubuntu 12.10 I had been using WBFS Manager but I had a .wbfs file that was not recognised. I tried Wii Backup Fusion but got the following error message in the log tab:
(Fri Nov 9 19:26:32 2012)
Wii Backup Fusion 1.1 started.
Wiimms ISO Tool not found!
Wiimms WBFS Tool not found!
Titles not found!
Finally I had success with QWBFS Manager v1.2.0 available from the Software Centre (Synaptic/Apt):
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Isn’t the better idea to actually install WiiMMS ISO Tool from their website?
A lot has probably changed in the 4 years since I wrote this 😉