I, too, am having difficulties getting a MIMO2+ successfully connected. I have an ISY944i running 5.3.4 with a 500 series Z-Wave interface. The MIMO2+ will join, but only two entries appear in the device listing: "ZW 011 Multilevel Sensor" and "ZW 011 Binary Switch". I'm not having success programmatically reading a value from the (only) sensor input - I can manually trigger a query from the admin console and the value updates, but attempting to read the value in an If statement in a program does not appear to be successful.
I've tried setting the MIMO parameter 3 (loading a value of 127) to send when change of trigger occurs, but although a progress bar appears when I apply a contact closure to the MIMO input (crossing the input threshold), my program does not sense the new value and execute. Again, if I click on the "Query" button for the device on the admin console, the new value does appear there.
Oh, and the second input and output are nowhere to be found. Is there some magic that can make this work?