There are quite a few settings that need to be set in order to make this properly. It is also recommended that your M-Series device and your iPad have Static IPs or you have to reset the addresses in both programs at every boot.
In MPC, go into Menu -- Network -- OSC -- Settings. Click on for the ethernet interface that is connected to your wifi router. Make a note of the IP address and Port #. Go to the bottom of the screen and click Devices. Click one of the slots, and give your slot a label, device space (0 follows the MainPlaybacks. If you want your iPad to operate independently of this, set this to something other than 0). Make a note of this port #.
Open the TouchOSC app of your iPad. Load the MPC iPad layout, and click the OSC settings tab. The IP address is the address of the computer which you noted from the Setting Tab in MPC. Port (Outgoing) is the port # listed in MPC- OSC- Settings page. Port(incoming) is the port number listed on the Devices tab in MPC for the slot you picked. No need to touch the ZeroConf Name tab, and finally note the local IP address of the iPad. Go back to MPC - OSC- Devices tab, pick the slot your device is, and input the IP address of the iPad. Click Apply and Close Menu.
Back out of the OSC Settings Menu in the TouchOSC app, click DONE. You are now viewing the iPad template. At the top right, click on the last tab (the last one before the circle) and click refresh remote. Go to Tab 1, and you should now have bi-directional control of the program.