Can't seem to satisfy FM Go with the file name on the host (FM 12).

Had no trouble accessing the host from my MacBook using the fmnet:/......... address.

That apparently is not the way to access from the ipad.

After adding the host ip address to Favorite Hosts

I've tried

fmnet:/.......

<ip>/file name

<ip>/fully qualified file name

No luck.

What's the secret?

I don't know if this will help you.  it's what I did.  Create a new DB with no records. Under security apply the same username and password that is used on the hosted file.  In the scripts create a startup file with "Open File". under specify add the filemaker data source.  Now under file options set this script to run on first open window.  I also have the script close the file.  Now each user can open the hosted db after I send them the opener file by email.  They install directly from mail to the ipone as a local file.  should the host connection time out they can tap cancel and then tap the opener file for quick login....  In my case I also pass multiple parameters to control what happens after the hosted file is opened, but that was not what you asked for.