CST MWS - Subgridding

Hello,

I wondered if anyone has tried using subgridding in CST MWS 2008. It seems to work if you have a high permittivity material inside a low permittivity one (e.g. vacuum) but cant get it to work the other way round.

Any suggestions appreciated.

[more info...]
{I am trying to simulate blocks of SiO2(permittivity 3.90) inside a silicon(permittivity 11.9) substrate. I have placed a series of fixed points inside the SiO2. I have tried playing with multiple options in the 'Specials' of the mesh properties but the high density mesh always comes out on the silicon (bulk). What i need is for the blocks of SiO2 to be meshed more finely than the bulk Silicon. If i reverse the materials (ie put blocks of silicon inside an SiO2 substrate) the mesh comes out correctly.
Also noticed that the local mesh properties are greyed out. Wondered if anyone knew how to enable these.}

Best Regards,
CD.