When you install SiteEdit 2009, you are creating a new web site in IIS (on the same machine where your Tridion Content Manager is installed). This web site (often called the SiteEdit proxy web site) proxies incoming requests between your staging site and your Tridion server.
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It looks to me as though your font is getting used, but is displaying the wrong output. The obvious suspect here is an encoding issue. Are you using UTF8 everywhere? I would suggest checking the configuration of the proxy site, and also the response headers to ensure they are correct. (Presumably in this case, "correct" means "the same as on the live site".)
By default when you install Tridion 2013 sp1 then XPM will also be installed and hence you have to use Tridion 2013 sp1 owns XPM and if suppose you try to incorporate the old version of site edit in 2013 sp1 then that will not be supported.
And also why do you want to use some old version of XPM with latest Tridion version as you could achieve more features ...
SiteEdit 2009 uses a single Page TCMURI for tracking the current page. It neither has the option to work without a page, nor to work with multiple pages at the same time.
So no matter where the Component Presentations in the HTML come from. For every CP it checks whether it can find that Component Presentation in the current Page XML in the CMS.
If it ...
No, SiteEdit will not work with SDL Tridion 2013 or higher. You can upgrade to Experience Manager relatively easy (need to change the Building Blocks in your templates, and republish), and if you don't use Session Preview there's not many infra requirements (I do advise using Session Preview though, only suggesting this to accelerate implementation).
tl;dr: ensure that your web server serves a Content-Type header for your custom font.
When you access your web site through the SiteEdit proxy, that proxy potentially parses all textual content for SiteEdit tags. This means that the SiteEdit proxy ends up reading the text that your web site serves and writes it out to the browser. It seems that your text ...
Can you try by creating a sample HTML and executing on the Server and see if this font loaded or not. If not, can you try by registering the Font Family in OS (or may be if it is already registered, then Un-registering and re-registering it)
Couldn't you template out a list of component IDs being used on the Page. Then you can insert your extension logic to retrieve this value and build the dialog as required?