...
...that's about it. I know nothing about them. This one seems well put together for its age.
It has a strange seat tube problem I've not encountered previously, but I hope to get that sorted.

Also, I presume the routing for the front derailleur cable runs under the BB shell and up through the angle purposely set nto the stay bridge. I can figure out no other solution, unless the frame is missing something, and I can't see where anything has broken or fallen off. Thanks for any information or references.