Share 'Terraforming Problems'

Can anyone give me tips or advice on best way to terraform in OL? I can manage it perfectly well in SL, but it doesn't seem to work so good in OL atm. For instance, I find the easiest method is to "select" the area of land and apply to selection, but that doesn't always work. When trying without the select tool, it seems to be pretty much hit or miss!! Any tips would be much appreciated. Thanki...