Overarching plot progression (Spoilers, lots of Spoilers)

Catching up a bit, we appear to have three consistent storylines/themes going on:

1) The Committee and The Red Key, and their involvement with Torchwood.
2) The New Torchwood of 2015/2016/2017, leading in to Aliens Among Us.
3) Torchwood through the Ages, showing us other eras and teams of Torchwood past.

releases, and their ties to these three strands, are as follows:

BFTW01 The Conspiracy introduces us to The Committee, which is the big through-line of the range thus far. We also meet George Wilson, book circuit conspiracy hack (except he's right about a lot of it, unbeknownst to himself). Jack goes underground to track them down, leaving the team to fend for themselves for a bit. Apparently takes place early/mid Series 1.

BFTW02 Fall to Earth follows Ianto while Jack's away due to the events of the previous play, caught up in another Committee plot, possibly inadvertently coming across one of Jack's hideaways in the process.

BFTW03 Forgotten Lives skips forward in time to half a decade after Miracle Day. Jack has struck a deal with some aliens who once successfully staved The Committee, and it's all gone horribly wrong. We find that The Committee was apparently pulling the strings behind the events of The Miracle, tying them into events seen in the show proper.

BFTW04 One Rule skips back to March of 2005, and follows Yvonne Hartman long before the events of Army of Ghosts & Doomsday. She, too, gets caught up in a Committee plot to control some local politics around the Cardiff Rift (and quite possibly keep an eye on Jack).

BFTW05 Uncanny Valley jumps back to Series 1, and has Jack tracking down Neil Redmond, who was involved in one of George Wilson's conspiracy theories. From his evil robot doppelgänger we learn that The Committee isn't performing an invasion... they were invited here to Earth, a long long time ago.

BFTW06 More Than This flashes back forward to circa 2016 and follows Gwen a bit after the events of Forgotten Lives, setting Torchwood back up right and proper. No mention of the Committee in this one.

BFTW07 The Victorian Age jumps way back to 1899 or so, and has Jack and Queen Victoria chasing after a rogue alien through the streets of London. This alien has a strange age siphoning power and was apparently shipped express freight to a member of parliament by a suspicious organization... coughTheComitteecoughcough. Uncanny Valley did say they were invited here a long while ago...

BFTW08 Zone 10 follows up Uncanny Valley and sees Tosh travelling to Russia and the mysterious Zone 10. We learn that The Committee was actively working with the Russian equivalent of Torchwood around the time of the space race, and that when Russia rebelled, things went horribly badly for them. We also learn that, long before they worked with Russia, they worked with Torchwood, and there was a deal of some sort that they want fulfilled. Tosh is given an item known as The Red Key, a present from The Committee.

BFTW09 Ghost Mission is the most recent release. We skip back to 2016ish, and sees Sergeant Andy's Torchwood interview, of sorts. We actually get to see The Committee, or at least some of their representatives, and learn more about the mysterious Red Key...

BFTW10 Moving Target features Suzie Costello, trapped in the middle of a time-altered big game hunt on planet earth, with which The Committee has had a hand in behind the scenes.

BFTW11 Broken features... I can't quite remember, someone from The Committee had something to do with what was going on at the pub, yeah?

BFTW12 Made You Look had nothing to do with The Committee, as far as I can recall, but furthered the "2016 Torchwood" b-plot that's intertwined in some releases.

The Torchwood Archive was al about The Committee and The Red Key, and contained more info than I can summarize in a line or two. Notably, it revealed The Committee's origins, and it's ties to Torchwood. It also sneakily contained a flashforward with one of the new Torchwood members from the upcoming Aliens Among Us. It also showed us that various events happening in previous audio releases, like Department X and Ghost Mission, were tied to The Committee, as well as The Red Key figuring into things like the fall of Torchwood One seen in Doctor Who Series 2, Jack's involvement with Torchwood India as seen in Golden Age, and the very existence of The Weevils in the first place, among other things.

Torchwood: Outbreak may in fact be about a virus The Committee had cooked up and was briefly spoken about in a segment of The Torchwood Archive featuring Norton in an epilogue to Ghost Mission.

Torchwood One: Before the Fall doesn't have much to do with The Committee, as far as I recall. I was a bit distracted when listening to this one, so someone else will have to correct me if I missed something here.

BFTW13 Visiting Hours continues the 2016 2017 Torchwood plotline that now appears to be leading up to Aliens Among Us.

BFTW14 The Dollhouse had no Committee ties that I recall (admittedly, I was distracted), but begins a throughline of "Torchwood through the ages" that retroactively started with The Victorian Age and continued in The Archive, showing previous eras of Torchwood and other teams.

BFTW15 Corpse Day featured some of the most f@cked up stuff I've heard on audio from BF, and I'm a huge fan of their Confessions range. It's events were facilitated by The Committee giving a poor family a "child" to adopt.

BFTW16 Cascade might feature some Committee connections, but nothing explicit. It's bloody good though, so go listen to it anyway.

BFTW17 The Office of Never Was, again, features the aftermath of The Committee kindly stepping in to help out someone, this time an office block in need of organization and efficiency training.

upcoming:

BFTW18 The Dying Room will be set in the 1940s, continuing the "Torchwood Through The Ages" story. It is as of yet unknown if it will contain any ties to The Committee.

Torchwood Series 5: Aliens Among Us will be the next full "Series" of Torchwood, with input from RTD, split up into three box set releases of four episodes each. It will follow on from the 2016/2017 Torchwood stories, and features a rebuilt Torchwood with new members, in addition to Jack and Gwen (and Rhys and Andy). It is unknown if The Committee will play any part in the story.