Mac fonts, there are a few different flavors of them. Mac OS 9 and prior had the fonts stored in the Resource Fork and not the Data Fork. When you buy a font now, the font is stored in the Data Fork.
Even if you still have fonts which are 10 plus years old. They are still not a problem when ONLY using SMB. I say only, because the file has to be copied from the Mac to the SMB share. When this happens, the Mac still writes the Resource Fork to the SMB share and the Mac will still access the font correctly.
What will NOT work. Copying the old font to the fileserver via AFP, unmounting the Fileserver. Then mounting the fileserver using SMB. Your font will show 0kb because the special Resource Fork wasn't created for use with this mapped SMB drive.
Exactly about the Mac fonts. It is hard to convince people that fonts work fine with SMB if you do it exactly as you described.