Older Clients cannot Authenticated to 10.10 Server ( Also SMB issues)

Hello

I am having a few issues with Server.app ( running on 10.10.2)

It appears older clients ( tested but 10.6 and 10.7) cannot log into the servers open directory. They can bind to it but cannot log in. If i log in with a local account they can still access file sharing etc.

10.10 clients are fine no issues whatsoever with logging in. ( i have not had a chance to test 10.9 and i don't have any 10.8 clients )

I am guessing its something to do with the way older OSs authenticate with the OD but i am not sure, don't have a huge amount of experience with OD outside of general admin.

My second issue is with SMB.

I am using SMB for file shares, everything was working well and then i started to have issues where users get a message saying the fire cannot be read or written error 36.

The file however would copy over no issue at all.

if i connect via cifs:// rather than smb:// it works ( this uses the older version of SMB ) but in an ideal world i would prefer if i did not have to use this as i would have to run a script on every client to force it to use cifs://

AFP works fine however i cannot use AFP for 2 reasons.

MS office for mac does not agree with it , accessing files over afp with this application causes files to be corrupted and become locked for editing. Apparently you need to have a globally writable folder called .TemporyItems in the root of the share for MS office to work correctly ( good design there microsoft) but this does not appear to work.

AFP does also not appear to make file inherit the permissions when you copy something into the directory so its no good for a shared folder .

Is there any way to force yosemite server to use SMB1 so i don't have to edit every single clients settings?

I would also be happy to use AFP if the 2 issues above can be solved.

This is so strange our old 10.6 server works just fine with MS office over AFP.