Tuning as in how? I've stayed with the 40gr CCI MiniMags as they run just fine. As I mentioned mine didn't like the 36gr MMs. I tried removing the smaller inner recoil spring but that didn't seem to make much difference so I put it back in. I will start trying other ammo as sometimes the 40gr MMs can be hard to find locally. Now that I'm past the 1200 round break-in, I will start experimenting too.
I also saw on the FB group that canuck223 isn't a fan of Frog Lube. After about 700 rounds of Frog Lube I started to cake and bind. I took it down last night and went back to Hoppes/MPro7. It's breaking in really nice with some very even wear patterns. I'll try some 36gr again this weekend.
My K22 Xtrim was a first generation X-Trim from Dlask, and worked great out of the box with 40gr Minimags and 40gr Blazer ammo. I wanted to make it work with a wider variety of ammo, so I progressed through a bunch of tinkering & tuning.
The slide was heavier that the current generation one. So I had some additional cutouts machined in to further lighten the slide and bring it closer to the weight of the new generation slide.
I did some polishing to the slide contact points to accelerate the break-in. Another area to polish was the hammer and increasing the radius of the corner of the slide that resets the hammer. That's something I picked up tuning my 10/22's.
The K22 mags from Dlask needed a bit of tuning too. The follower sometimes needed trimming to move freely up and down the mag, and the mag spring was very strong, so trimming 2-3 coils off helped reduced the pressure from the round pressing up against the spent round as the slide recoiled.
I did also reprofile the extractor. That probably was not necessary, but again that's something I'm just used to doing when I tune up my 10/22's & Ruger 22/45's.
I'm able to run a fairly wide selection of 40gr ammo now (except Winchestor Wildcats), but lighter 36gr/38gr ammo still results in the odd FTE. So I just save that stuff for my other .22 hand guns.