VM140, problem to use with Qt creator

Hello everyone,
I use a VM140 and until now I was using codeblock and coding in C++ to control its outputs and inputs. Using the example software provided with the card I was able to achieve this goal. Recently I had to go from the console mode to create windows. I changed the software to code and I now use Qt creator. My first goal is to create a simple window with button On and Off for each output.
The window with the buttons was successfully created but I’m not able to load the DLL in Qt and thus, I’m not able to connect the button.

In this purpose I created a project giving me a head file test.h and a source file test.cpp. The window created in test.cpp is launched with a souce file main.cpp.

Did anyone ever used Qt creator to do this?
Could anyone help me to load the library, and to connect a button with one function included in the K8061.dll?

Basically, I would like to do a window similar to the example one provided on the CD to control the card.

Thank you very much.