Robert: is that the "blue" Hylomar ? If so, that stuff never hardens, correct ?

My understanding is that the top timing-chain cover needs Hylomar on the gasket, but a hardening substance (e.g., The Right Stuff) on the edges that is "blowout proof".

FWIW, "The Right Stuff" is now Mercedes approved, and "blowout proof".

http://www.permatex.com/products/prodidx.asp?automotive=yes&f_call=get_item&item_no=33694

Excerpt (note last sentence):
Return equipment to service immediately when you make leakproof gaskets in just one minute with the Right Stuff.® This latest elastomeric rubber gasket technology is blowout resistant and outperforms pre-cut gaskets. Specified on production lines by GM, Ford, Daimler-Chrysler and Mercedes-Benz. Temperature range -75°F to 450°F; (-60°C to 232°C) continuous, 500°F (260°C) intermittent; resists ATF, coolant, oil and other shop fluids.

Protects against leaks caused by vibration and thermal expansion.

:-) neil