Yeah I know, I wish CD liner notes would point that stuff out too, would it really be that hard for them to do? I guess so.
Just as a guess, I'd say (in addition to the ones she sings lead on) she might be on:
Night life (cuz it was originally the B-side to the IRGB single)
Tell me (cuz of it being on "OK Ken" originally)
Lonesome whistle blues (cuz of it being on 40BFFPARTS)
The letter (for the same reason as LWB)
San ho zay (for the same reason as LWB & TL)
...as it does seem that Stan has tried to "bury the past" when soldiering on with new CS lineups so you'd think that he would've dropped these songs from his set lists pretty early on (if this was in fact what he had tried to do)
...but heck, "Strange things happening" was one that surprised me that she sang lead on as I didn't even know of this song existing until this CD so she probably is on some others as there are many old sounding ones (i.e. more trad than the blues/rock boogie that the Shack later went in to etc.) with chunky piano that sound like possible CM contenders and Stan's guitar being more restrained (unlike tracks such as "Telling your fortune" which, as an example, is a track that I'm certain she wouldn't be on and that it must be from the early 70's Shack (at the earliest).
Tracks like "Tired eyes" sound like they could have her piano work, I think I hear this more evident on the "On air" version of this song so it's just another flimsy reason I've been leaning towards since they won't give us good liner notes and we have to do this kind of assuming in the meantime.
Oh well, hopefully someday we'll find out for sure somehow.
John