I edited your file a bit in emacs (a text editor) to convert it into an mpd file.
I took the synthesized cable bits and the two 58124c01.dat cable end parts and moved them to the end of your file and added an mpd file header to tell lpub this is a part.
0 FILE pf_cable_part.ldr
0 !LDRAW_ORG Unofficial_Part
Then I added an mpd file header to the beginning of your file to designate the whole thing as an mpd file.
0 FILE lpubtest.ldr
And finally I added a line to include your new synthesized part in the main construction.
1 16 0 0 0 1 0 0 0 1 0 0 0 1 pf_cable_part.ldr
The resulting mpd file is here (apparently I lost the top 2 lines in my previous pastebin link).
Anyhow, I think you can create mpd files like this directly in mlcad and avoid using a text editor. But I'm can't tell you how to do that because my mlcad skills are quite limited.
I took the synthesized cable bits and the two 58124c01.dat cable end parts and moved them to the end of your file and added an mpd file header to tell lpub this is a part.
0 FILE pf_cable_part.ldr
0 !LDRAW_ORG Unofficial_Part
Then I added an mpd file header to the beginning of your file to designate the whole thing as an mpd file.
0 FILE lpubtest.ldr
And finally I added a line to include your new synthesized part in the main construction.
1 16 0 0 0 1 0 0 0 1 0 0 0 1 pf_cable_part.ldr
The resulting mpd file is here (apparently I lost the top 2 lines in my previous pastebin link).
Anyhow, I think you can create mpd files like this directly in mlcad and avoid using a text editor. But I'm can't tell you how to do that because my mlcad skills are quite limited.