The “driver” that is on the velleman website is not really a “driver” in the LabVIEW sense of an instrument driver, like you might get from NI. It is a sample program that uses some of the functions. The way it works is that the program makes calls to the K8055C.dll for each funtion. Here is the way to do that without using the sample program:
Download that K8055C.dll and place it in your \win32 folder (assuming you’re using Windows).
In your block diagram, place a “Call Library Function Node” (from the Connectivity pallet).
Right-click the node, and select “Configure.” In the “Library Name or Path” window, navigate to the .dll in the \win32 folder and select it. In the Configure window, select “Call any UI thread” and "STDCALL (winapi).
Select the function you want to use, then configure the Parameters on that tab, then click Okay. The parameters you select will be available as inputs and outputs on the node in the BD, so connect your controls and indicators to those.
Be sure to Open the device at the beginning, and Close it at the end.