[Bug when searching for Overextended Mod]

This seems to be more a bug with mods you had equipped and took them off while editing a build.  If you search for some of the mods you removed during the current editing section then the search wont find them.  A workaround if a mod comes up missing is either to manually find it in the list, or to exit the arsenal and search for it again... It should show up normally afterwords.

[Reckless Combination mod isn't working.]

The Reckless Combination mod which should tick up extra combo count on each instance of slash status proc damage isn't reacting at all to slash procs.

I tested three different melee weapons and the combo wasn't affected, neither by proc nor the slash status' damage.

[The K-Drive launcher gained after Vox Solaris is no longer Available]

It is indeed a problem that has turned up with a few people, and there seems to be no reliable way to regain the launcher short of a fix for it.

Lost mine a couple days after Fortuna launched, looked into my gear to change around it's order and it turned up missing. Luckily I still have a bunch of other stuff I have to do aside from Fortuna.  It is a bit of a downer not being able to use the new K-Drive though.

I'm sure they'll get around to it.  As major of an issue as it is, relatively few people seem to be having it compared to other stuff.

[K-Drive launcher lost]

Seen a couple of posts saying if you get a new board that it restored their launcher, but also seen a couple that have said they tried that and it didn't work.

Would be better off waiting for an official fix in this case. You could end up burning plat/standing on only a chance when you can't really get more standing until you get the board back proper.

[K-Drive launcher lost]

Can't say for him, but for me, I had it in slot 2 right after my Archwing in slot one.

Had been using the K-Drive on and off with no issues, then switched to mainly Archwing to grind bounties as they move faster. Having always had my scanners on the first slot and only having changed it to fit in the K-Drive, I decided I would move the Archwing to 2, and the K-Drive to 3, and put the scanner back on 1.

That is when I noticed the launcher was straight up gone from the gear list completely, and the slot that is was in was also empty as though it had just been unassigned.

[K-Drive launcher lost]

You aren't alone, while I have not built a custom K-Drive yet, I too have lost the launcher for it.  I've seen others saying they have also randomly lost their K-Drive launchers though I've seen no post nor legitimate fix for the issue yet.

Lost mine a couple days after Fortuna launched and, like you, tried to replay Vox Solaris to no avail.  Given how few of these posts I've seen (Like maybe only one every 2 or 3 pages), I would assume whatever triggers it isn't all that common.

[Some paths for the 'Escort the Drone to Safety' objective stall.]

A few paths for the Plains of Eidolon 'Escort the Drone to Safety' objective will result in the drone either getting stuck on a cliff or flying up into the air then stopping all movement.  Generally it seems the paths for them are specific routes from one area to another, and some have the issue occur more often than on others.  One of the more notable routes that almost always has an issue is the one from Gara Toht Lake up through Hek's Stiletto and then around the lake toward Seaside Ruin. The drone will, more than half the time, start on the way up to Hek's Stiletto and just before the first Vruush AA Turret take a right off the cliff where it can often stall and get stuck.

When this happens the only way to fix it is either ram into it and hope you can bump it free, or hope that enemy fire will somehow dislodge it. If it stalls at a point where it would have spawned enemies to contest it, enemies will constantly spawn every half minute or so as you kill them.  If you are unable to bump it free from where it gets stuck, it seems the only option is to fail the bounty/incursion and try again.

The stall points seem to usually be when the drone somehow gets airborne.

[K-Drive has a seemingly rare chance to disappear from gear inventory.]

Played around on Vallis for awhile, using the K-Drive after having equipped it in the gear wheel and everything worked fine for a day or two.

At one point after I went to take a break I noticed the K-Drive launcher was missing from my gear wheel. I went back into Fortuna and looked through my gear to place it back on the wheel, but it was missing from there as well.  Heading back up to the orbiter didn't help either.

Looked around on the forums for other people having the same issue, and there are a few people, but it would seem to be a rarer issue.  A few of them have fixed said issue by buying a daily special board with platinum, but if someone wanted to fix said issue without platinum they would need to grind the Vent Kid standing which is impossible without actually using a K-Drive. As a test, I reran the Vox Solaris quest to see if I could get one re-rewarded, however it didn't work.

[operator sigil flickering in fortuna (and missions?)]

I have noticed this issue as well, it seems to occur on transfer out animation. If you go to operator on the Orbiter the Sigil is fine as the animation is from the chair. Transfering out in Cetus or Fortuna will end up with this flickering sigil effect. If you go to customize the operator and change anything it refreshes the textures it seems and stops the flicker, but only until you transfer out again. Occasionally a transfer out wont end up with said issue, but it seems to stick once it happens.