1) I'll second what @Vinish
I replaced -- once, so far -- the bushings on '12 XCT. I used the factory nylon(?) bushings for my replacement, because I'd read too much about the tight tolerances of the metal ones, where many people using those replacements had to use sandpaper and suchlike to make them fit correctly. I'm not saying that that's a lot of work -- the sanding -- but I just didn't want to deal with it.
And the degree of side-to-side slop isn't particularly bothersome to me, but I could see, after a few years, that it was getting worse. I would generally check this side-to-side slop whenever I was at a Vic dealer. All the brand new floor models seem to exhibit this.
Which brings me to one question for you: what prompted you to change the bushings, in the first place, on what I gather is a fairly new bike? Not trying to be a smart-ass here, just trying to gather information.
2) Back in 2012, I had trouble downshifting my brand new XCT for a few weeks. I thought something was wrong, but eventually figured out that I was not letting my foot rise HIGH ENOUGH between shifts.
That is, the distance required for the lever to move GOING UP, to complete the shift, was much longer/higher than on any other bike that I was used to. (And I've ridden a fair number of bikes, as a result of my being an old geezer, riding demos at Americade by me, and also a former MSF instructor, with maybe 20 bikes to warm up before each class.)
Let's say, coming to a red light, I might bang down through three or four gears, all the while holding the clutch in and not letting out, to get to first. I would get locked into, say, second gear a lot. The solution for me was to just make sure I was raising my foot higher than I was doing, in between stomps. This worked fine for me, and I no longer had the problem. (Yes, there are linkage adjustments and that sort of thing you can make too, but just raising my foot a little higher, to let the shifter complete its "throw" on the up-tick, did the trick for me, and became a simple habit change.)
3) You might want to make sure the clutch freeplay is set to the proper specs. There's something in the shop manual on this, and I also recall it's covered in at least one of WitchDoctor's videos.
4) I have no idea why you're getting an error code. Haven't heard of that before, with respect to shifting. Maybe you wound up lugging the engine too much, and the computer eventually complained. You shifting at high enough RPMs (which is less than sport bikes, certainly, but higher than your typical H-D)?
5) Once you do get this resolved, the neutral finder on these bikes is a really nice feature. That's the one where you're stopped, and you can just flick up, and you're in neutral, instead of worrying about going into second. I think Kawasaki popularized this with a bunch of models over the years, but the Vics do it well, too. Just keep in mind that when taking off, you want to going at least 10 or 15 MPH before shifting to second; if you try to shift at, say, 5 MPH, the neutral finder would still be doing its thing.