This is going to be a very short and dirty guide, I hope I got everything right, i'm at work so i'm doing this quickly.
I won't go into texturing and manually unwrapping, that's more advanced than needed at the moment. What I will do is tell you how to convert a model from .obj to .x in Blender, give it a temporary AO (white shaded) texture and put it in GameGuru.
Before we start however, I do have to tell you that I downloaded that model and checked it out, the scale is fine so that's not your issue, but you won't be able to use it in GameGuru as it has waaaay too many polygons, the max for a GameGuru model is around 22,000 tri's, that model has almost 6 times that being 106,000 tri's. It just won't work in GameGuru.
That aside for future reference here's a quick guide:
1. Delete the default cube
2. Select file > import > wavefront (.obj) and import your model
3. In object mode - highlight all objects in the scene (press A a couple of times until everything has an orange or red outline), then press ctrl+J, this joins all the objects as a single mesh, this doesn't really need to be done if you're not animating as, but if you're animated with bones it does because sometimes when you have multiple objects with bones they don't "stick" together and end up in a pile on the ground in GameGuru (it's the same in unity too), but for the purposes of this guide i'm getting you to do it so we don't have to mess with multiple object UV unwrapping, which can be a pain.
4. Press TAB to get into edit mode
5. Press A a couple of times until everything is highlighted in orange.
6. Move your curser to the bottom left of the 3D window where there is a small triangle, hover over this and your cursor will change to a plus sign, click and drag the triangle to the right about half way across the screen, you now have two windows. (see picture attached)
7. next to the triangle you dragged is your current editor type button, click this and choose UV/Image Editor
8. Click on the New button and a box will come up to create a new image, choose the name you want to call it and the size you need and click OK
9. Now with your mouse hovering over the 3D view widow, press U, this brings up the unwrap options, for the sake of this quick epxlenation (you can explore the other options at your own pace) select Smart UV Project and click OK, you will now see lots of lines inside your image in the UV editor screen.
10. Go to the right hand side menu and make sure you are in the render menu (icon looks liek a camera at the top of the menu), then scroll down to bake. From the bake menu change the bake mode to ambient occlusion, tick the normalized box, and then press the bake button. This will ceate a greyscale image in your UV editor, this texture basically adds the self generated shadows for the model ie where it is darker under wheel arches ect. But we're not using it for that, we're using it as a temporary texture to see how it looks.
11. In the UV window select the image menu and choose Save as Image to save it.
12. Go back to the 3D view window and hit tab to go back to object mode, make sure everything is highlighted and press ctrl+A and select scale.
13. Now with the object still highlighted head to file > export > DirectX (.x), at the bottom of the left hand menu you will find some options, untick the material option, you sdon't need it and it causes models to be all black in gameguru, now choose your name and location and hit the export button.
Now go into GameGuru and use the built in model importer, this wil give you some files, the ONLY files we need from there are the BMP thumbnail, the FPE, your .x file, and the texture file you saved in blender, the rest can be deleted. We only used the importer to generate a thumbnal and FPE file.
Now, you should have the following files in a folder in your entity bank (we'll call the files "car" for now:
1. car.bmp (a 64x64 thumbnail image)
2. car.png (your temporary texture)
3. car.x (your original .x file)
4. car.fpe (the command file generated by gameguru's importer)
1. Open car.fpe in notepad
2. Find the line that starts with "desc", change the name after it to car
3. Find the line that startes with "Textured = " and change the texture listed after it to car.png
4. Find the line "Model =" and change the model name to car.x
5. Save and close notepad
Your model should now work in gameguru.
Here's the video tutorial series I used to learn how to create and import models for GameGuru in Blender, ove rthe course of the videos he explains in detail how to build, unwrap, texture, and import models into GameGuru, it's really well done, watch the whole playlist and you should understand how it all works much better:
https://www.youtube.com/watch?v=nPgQfd5bb4g&list=PL2fWo8eoaiUZpZDk5hNqwKTuQXWT8hm3f
(don't be put off that he calls it FPSC reloaded and not GameGuru, FPSCR was the temporary name for GameGuru at first release, it's the same software just a little older, but everything in his videos works fine with GameGuru now)
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