Since all driver configuration must be done in the Offline Development Xpress Manager Software, it includes a limited duration runtime connection to the PLC.
The later versions of Xpress (~2.15 and up) have a connect button at the home screen of the project editor. Pressing that button initiates the runtime connection to the PLC from your PC.
In versions <4.x there will be a Com Server icon show up in the Windows system tray that can be opened and used to view the connection error log if there are problems connecting to the PLC.
The runtime will run for about 1 hour and shut down.
Version 4.x> does not have the com server icon and runs as a service and any debugging beyond testing the screens has to be done using the "Message Display" tool in Xpress to show system messages during runtime.
IMPORTANT - Do not let the runtime on the PC go until it times out if running version 4.x> Since the com server is running as a service, the only way to restart it is to reboot the PC if the application is allowed to run until the com server shuts off.
Once you get the application running on the development PC, as long as the HMI has properly configured IP address and ports, the application will run on it. If it does not, then you would need to check your cables, IP address to be sure it is in the same subnet as PLC, make sure the IP address is not conflicting with any other units and if using the configurable Com Port (Com2 on XPR/XPR2 and Com1 on XT) that the port is properly configured for the driver you are using.