Well, if it was that simple to "update" SmbFS to SMB2, Olaf "olsen" Barthel or anyone involved in SmbFS from MorphOS Team would probably have been looked into it by now.
We are well aware of the "SMB1 problem" but there is no elegant short-term solution to it for now. I worked on some aspects of the MorphOS port but personally I would probably go for a full rewrite instead of messing around with the old code.
Maybe some "3rd party" is able to look into some solution using FUSE compatible filesysbox.library, AFAIR there has been some SMB for FUSE solution but I never really looked closer into it.