I believe that the correct I/O server is ABKF2 as BJH stated - you should have a "Device Integration" disk that came with Intouch. Hopefully you have the I/O Server licence too, although I'm not sure if you need one for the ABKF2 server. I also seem to remember trying to run this on a 64 bit machine with not much success.
Personally, I'd be looking to get a NET-ENI for your ML1500 so that you can talk to it over Ethernet (using wonderware's DASABCIP device driver, which you do need the I/O server licencing for) rather than a serial connection.
one other thing - I seem to recall having problems reading I/O directly, i.e. I1:0/1 or O2:0/1. What I normally do anyway is use MOV instructions in the PLC to move the state of my real I/O to another file, for example N9. That way I can expose only the info I want the HMI to be able to see / manipulate.
I don't have a micrologix around that I can fiddle with until late next week (new project). Could have a bit of a play then if you still haven't got it sussed.
I'd start with getting the I/O driver first. Once you've done that, set up your WonderWare topic and test that first by assigning a tag to one of the I/O server built in status tags (check the documentation for the I/O server). Then try reading a bit in a default file like B3 or N7 - I assume you've got the PLC program and RSlogix500?
