I dont believe you have to downgrade your Wii to 3.2 to fix that bug. I just used this guide NEW AND IMPROVED WII SOFTMOD GUIDE ! which I think is the easiest well put guide ive seen so far in learning how to mod my Wii, even with all the help ive gotten from everyone nothing compares to how easy this guide is. I litteraly softmodded my Wii in the amount of time it took to update to 4.1 +5-10 minutes to follow the guide for the first time.
1 of the steps said it was going to downgrade some IOS and patch them with the bug fix so I guess if thats what your looking for theres no need to go down to 3.2