Not a problem
You do know that in the new plugin system you can do all this in the new plugin system without altering any of the code right?
Say for instance you want a link under the image for your ecard thing the you would make a new hook on say the showphoto_below_image location and the link would show there. I do not know how your formatting the link so not like I can post exact details but it would look something like this
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Note I am just guessing what your doing but you can see how with that example I am generating the link in the provided spot.
What you do would depend on where your showing the link and how your formatting things. The point being you want to use the plugin system so you never directly hack the files and upgrades are easy.