So I looked into it more and apparently software rendering typically means the program is using the CPU instead of the GPU, which is obviously inefficient. It could be a driver or hardware issue. Have you updated your graphics driver recently?
Also, it could be an issue with Ren'py using the wrong renderer for some reason. I saw these instructions on the Ren'py documentation you could try, which I assume works for any game made in Ren'py.
- Hold down Shift while starting Ren'Py, or press Shift+G once Ren'Py has started.
- From the "Graphics Acceleration" menu that appears, choose the renderer to use.
- Choose "Quit", then restart Ren'Py.
Please let me know how it goes!