By design the windows client will not allow the users to create / move files or folders that commulate to such long path.
when does it allow it? when it' can't determine it.
So you need to aim for having the Intellisnap to use the same path or shorter one then what the client uses. either by different share name. not using FQDN. setup a cname. get somehow Intellisnap to mount it, or maybe change how the clients accessing it to be long enough for windows to block it.
if you try to limit the path in the filer itself, that again relative to how the filer see the path, and not 1:1 match to how the user and not how Intellisnap exactly see it (unless you hard code it in your solution whatever it will be) .