The KTOR book will answer these questions in more detail than I can here.
The Scarlet Ribbons single is the celeste one you mentioned. The Trio's first ever 45 release. It was later re-recorded for At Large .
The three songs from the Hungry i album that you mentioned were all previously recorded in the studio, but the a capella introduction from the studio version of Gue Gue was actually dubbed into the live version that appeared on the Hungry i album.
These three studio versions were first released on The Guard Years CD along with other unreleased mono recordings from the same period circa 1958. Never on vinyl.
The liner of the new CD did not mention that Como Se Viene, Se Va was released in Duophonic on the British Tribute To The KT vinyl album which I got from England when it was released.
EMI issued this one in the UK instead of Best Of The KT Vol III.
Some years ago I sent a copy of this album to Shane who said that he preferred this compilation to Best Vol III .