Leo4All users still wait for eddie11c`s combo update, but they don't have to. Leo4All can be updated with Kalyway combo update and it works for all processors AMD and Intel (SSE3 required). Guide can be found here. Kalyway warns of problems with Nvidia 7xxx cards, but all you will have to do is to reinstall your graphics drivers to get your QE back. There are some other issues as well, but if you want to have 10.5.3 right now go for Kalyway.
For graphics problems you have to use a different driver than NVinject, somehow it doesn't work well with 10.5.3. A working solution for that is NVkush driver. After installing it you will have to delete NVinject form Extensions folder and repair permissions with Extensions-Repair or with terminal and finally reboot.
Crashing "About This Mac" Window - Solved When you install Kalyway Combo Update you have two options, to keep your old kernel (9.2.0 or 9.2.2) or install the new Modbin 9.3.0 kernel which works with both AMD and Intel processors.
Modbin kernel does not support sleep / hibernation so you will miss that function if you got it to work under 9.2.x kernel. But keeping the older kernel will make your System Profiler crash every time you open it. So if you need this sleep functions, keep the old good kernel and wait for a new ToH kernel.