Three questions on hyperlinking and conditional formatting
 

First question is how do I hyperlink directly to a "comment" in another
workbook.

Second is a little hard to explain. I need to be able to type text (say
av123) in a certain cell (say D64). I need to search a group of cells
for this exact text of "av123". But that cell that contains this text
(say E12) may contain the full text of "ad76", "av125", "ad12",
"av123". I need to conditional format this cell with a color. In
essence I am using the cell D64 as a search box to search all cells of
a worksheet.

Third. I would like to be able to correspond 2 different cells together
(say B1 and E40).
And just by clicking on one of these cells will cause both of them to
be formatted with a different color. And by clicking any other cell the
formatting would change to normal.

Any help in any of these would be appreciated...especially the first
one.