I've decided that rewriting url's is too complicated for me and I can be content with "/page/", in addition to performing 301 redirects for all my old, pre-blogengine pages.
For other simpletons like me:
For each page you want to redirect, just create an aspx page in the root folder using the old name, but add this script:
private void Page_Load(object sender, System.EventArgs e)
Response.Status = "301 Moved Permanently";
Response.AddHeader("Location", BlogEngine.Core.Utils.RelativeWebRoot + "page/NewPageName.aspx");