Just went and looked to see if the braces could be mounted on one side of the MFT Kapex similar to the way they mount to the MFT-3 and the answer is . . . “Maybe”.
The crossbar on the leg assemblies is at the same location, so that wouldn’t affect the fit.
I measured the distance between my two mounts where the braces on my MFT-3 connect to the bottom of the rail to come up with a space of 290mm.
When I compared the rail lengths of the two tables, I came up with a 288mm difference. (Festool specs for the two also show 288mm of difference as well.
Those brackets are adjustable as to where they mount on the rail, so you can definitely make it work on one side. If the brace was a little two long, all one would need to do is slide the mount that attaches to the leg crossbar away from the leg until the brace fit.
Clint