Here is the BTX server software as a zip file for download: btx_server.zip
Installation and usage instructions are included in the zip file. The software is still at a very early stage and still buggy, but you can call up a BTX page via *page# like back the old days. So, there is more to come ...
If you are a lucky Mupid owner, try out my Forth interpreter for that decoder (actually a FIG Forth port). Start the BTX server, change to the forth directory with "cd forth", press the blue "K" and then "A" on the Mupid, and then call up the BTX page with "*mupidforth#". After some loading you have the old interactive programming language Forth available for your own Mupid experiments.
And here is the server in action showing an old German BTX page on my Mupid, a cool Austrian Videotex decoder from the eighties: