Salut Hervé,
I found a mistake! When I extract the Bootpack, there is the file kernel.plist in the folder Extra. The file is not in the right format (maybe you can change that?). After the correction, I was able to boot.
kernel.plist before:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict/>
<key>KernelBooter_kexts</key>
<string>Yes</string>
</plist>
kernel.plist changed (hopefully correct)
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>KernelBooter_kexts</key>
<string>Yes</string>
</dict>
</plist>
Now I have post boot Problems. I will report and ask for it. Before that, I will search myself for a solution.
Merci beaucoup!