Get value of property from other page type in transformation
in source code, AppCode/Custom/Transformations/Transformations.cs
public bool IsHeaderTranslucentEnabled(string aliasPath)
{
bool enabled = false;
TreeProvider tree = new TreeProvider(MembershipContext.AuthenticatedUser);
TreeNode node = tree.SelectSingleNode(SiteContext.CurrentSiteName, aliasPath, "en-au");
enabled = ValidationHelper.GetBoolean(node.GetValue("ShowHeaderTranslucent"), false);
return enabled;
}