OK, great! I've just rebuilt an amd64 netinst image, bundling the extra module inside (/lib/modules/6.1.0-7-amd64/kernel/drivers/platform/x86/intel/intel-rst.ko) and I've verified that this module loads fine in a VM.
Hi, I made an installation test, but no change. In the shell of the installer lsmod does not list intel-rst as loaded. I think that there is more necessary than just providing the module. Don't know what the Ubuntu installer does. At least a hint in the installation guide would be nice to switch off the RST RAID mode in the BIOS if the HDD is not detected.