Convert code from a static html to place into a repeater

1: Although a bit messy (you may want to create a Custom Transformation Method to contain this logic)

If(Eval<int>("NodeOrder") > 1, CMS.DocumentEngine.TreeHelper.SelectSingleNode(Eval<int>("NodeParentID")).AllChildren.Where(x => x.NodeOrder == (Eval<int>("NodeOrder")-2)).FirstOrDefault().NodeAliasPath, "")

2:

Since you want to go beyond months, i would recommend you create a custom transformation method since the logic is hard to fit into 1 line, but if you did want to...it would look like tihs mess

CMS.DocumentEngine.DocumentHelper.GetDocuments("CMS.BlogPost").Path(CMS.DocumentEngine.TreeHelper.SelectSingleNode(Eval<int>("NodeID")).Parent.Parent.NodeAliasPath+"/%").OrderBy("BlogPostDate").Where("BlogPostDate > '"+Eval<DateTime>("BlogPostDate").ToString()+"'").Take(1).FirstOrDefault().NodeAliasPath

With the note that the above will ERROR if it's the latest blog post since there isn't one that beyond it, hence why a custom transformation method that can check to see if the object is NULL before calling it's NodeAliasPath would be helpful.

Is creating Custom Transformation Method available in Kentioc 7. Im googling the documentation to create one.

This should be the documentation on how to create custom methods for transformations in K7

You'll probably need to adjust my logic then, i put it in Kentico 10, so the methods and classes are probably a bit different, Kentico 7 is pretty ancient.