GP4: Guide to Zaz Tools - CSM process update

Some of you have had issues with my recent mods (1994 v4.3, 1993 v2.0 and the 2025 mod) which rely on injectdll to function correctly.

You can read more about the benefits of injectdll here: GrandPrixGames.org.

This tutorial brings together everything I know about getting the setup working correctly for those who are still having problems.

1. Check your Grand Prix 4 installation

One of the first signs that something is wrong is that the high-resolution fonts appear oversized.

If this happens, other DLL-related tweaks such as individual cockpits and tyres will normally fail as well.

This is usually an installation issue where GP4 still thinks it is running the original unpatched version, even if you have already applied the patch. These mods are designed to work with GP4 v1.02.

If you are having this problem, I recommend starting with a fresh GP4 installation:

GP4 installation hosted by Carl_gpgames

Alternatively, try one of these:

1. GP4 Installer (ISO)
2. Simple GP4 Installer (EXE setup)
3. Portable GP4 folder (7-Zip)

2. Make sure you are using a decrypted GP4.exe

You also need a decrypted GP4.exe.

If you don't already have one, you can download it here:

Download decrypted GP4.exe

You can replace the executable in your Grand Prix 4 directory with the decrypted version.

Alternatively, I keep it in my Grand Prix 4 folder as GP4_old.exe. In CSM you can then select GP4_old.exe from the drop-down menu next to the Exit button.

3. Check your installation directories

This guide assumes that Grand Prix 4 is installed in its original default location:

C:\Program Files (x86)\Infogrames\Grand Prix 4

GP4 itself should also work if installed elsewhere, but the path becomes particularly important when using CSMProcess.

For ZaZ Tools, I recommend using its normal installation directory:

C:\Program Files (x86)\ZaZ GP4 Tools

The steps below will deal with the brackets in Program Files (x86) when we install CSMProcess.

4. Install ZaZ Tools 1.27c

Install ZaZ Tools 1.27c, preferably in its default location:

C:\Program Files (x86)\ZaZ GP4 Tools

Download ZaZ Tools 1.27c

I've found that ZaZ Tools also works best with the following compatibility settings. I have used these successfully in both Windows 10 and Windows 11.

I also had to create an antivirus exception for the entire ZaZ GP4 Tools directory.

5. Install CSMProcess

Next, install the modified ZaZ Tools package containing the CSMProcess update:

Download ZaZ Tools 1.27c Modified / CSMProcess

When you run the installer, it will place csmprocess.exe into your ZaZ Tools directory, so make sure you direct it to wherever you installed ZaZ Tools.

If you use antivirus software, you may also need to create an exception for this file. If you have already excluded the whole ZaZ Tools directory, this should not normally be necessary.

The installer will then ask where Grand Prix 4 is installed.

CSMProcess will check whether the GP4 installation path is suitable. One important issue is that CSMProcess does not work correctly with brackets in the path – most notably the (x86) in the standard Program Files directory.

If your GP4 installation is inside Program Files (x86), the installer will create a directory junction. This allows the same GP4 installation to appear at a simpler location such as:

C:\Grand Prix 4

Once the correct path has been selected, click Install.

6. Check the CSM paths

Finally, check that CSM has updated its GP4 paths correctly.

If it has not, you may need to edit the paths manually.

The important point is that the path used by CSMProcess must not contain brackets.

For example, rather than:

C:\Program Files (x86)\Infogrames\Grand Prix 4

CSMProcess can use the junction created by the installer:

C:\Grand Prix 4

Ready to go

If everything above is set up correctly, CSMProcess and injectdll should now be able to work as intended, allowing you to use the additional features included in my recent mods.

If you're troubleshooting an existing installation, I would work through the steps in order rather than changing several things at once. The oversized-font problem is particularly useful as an early indication that GP4 itself isn't being recognised correctly.

Keep racing!