A conversion alone usually is not sufficient for use going forward. I would read the migration tech briefs.
Looks like i've got a bit of bedtime reading to do!
In addition, at the earliest moment you can, use Manage | External Datasources to review any external datasource links between your converted files. Old versions of filemaker did a truly terrible job of managing these references. You may find a lot of "junk" that you can delete/edit in order to speed up how fast the files open over the network.
Two types of entries add many minutes to the connection process:
References with *
Defunct IP address references
Editing these references to replace them with valid IP addresses or DSNs can shave massive amounts of time off the file open process for some databases.
Are we at this one again?
pg. 34 on the fm7_converting.pdf discusses File References and poor performance.
I point users to the Tech Brief because if they do not read it, they will miss out on a lot of crucial information with File Reference clean up being just one thing. So the best solution is to tell them to read the briefs and not just suggest to do one particular thing.
My memory must be lacking. I didn't recall any discussion from the migration tech briefs that covered the data-source issue and so made that post. I was trying to supplement your post--not detract from it.