Opening the right version of GUIX Studio from e2studio project

Hi,

I installed two sets of software on my PC:

1) e2studio 4.2 + GUIX Studio 4.29 (SSP 1.1.0)

2) e2studio 5.0 + GUIX Studio 4.3 (SSP 1.1.1)

When I import a project on the newer e2studio 5.0, if I double-click on the .gpx file in the project tree, it is opened with the older GUIXStudio 4.29. Obviously I get an error: "THis project was created with a newer version of GUIX Studio...etc..".

I tryied to change the default program associated with .gpx extension, but it doesn't work.

How can I set the right version of GUIX Studio to be launched when I open a .gpx file connected to the active project opened in e2studio?

Thank you, Best regards.