UPDATE:
KJP (the dealer) sent me a second Colliflower fence which - prior to shipping - they tested to ensure the stops from their Kapex saw fit.
However, when I received it I found that while both of the stops from my saw would fit in one side (left) of that second fence unit (one reversed of course) neither would fit in the other side (right).
I felt that this second unit was likely closer to the mark than the fist, so I set about filing on all the way surfaces (slots, faces etc) of that fence. I also cleaned up the sliding surfaces of my stops with fine emery paper.
After about 3 hours of carefull filing of the Colliflower fence, I acheived a good free sliding fit with essentially no slop (ie the stops both slid properly and stayed vertical).
My conclusions are:
1) There is enough variance in different units of both the Colliflower fence AND the Festool stops to cause incompatibility.
2) I suggest that you take YOUR stops with you to a dealer and test fit to select a Colliflower fence unit that matches your particular stops. Alternatively order a couple of the Colliflower fence units and kep the one that fits best.
3) Be careful with the filing - if you overdue it, the stops will lose their alignment.
4) The root problem here seems to be the stack-up of machining (or extruding) errors on the Colliflower fence unit and the thickness (or "splatter") of the brown powder coating (or anodizing) that is applied; essentially you're going to need to remove any of that brown coating material from all of the sliding way surfaces of the Colliflower fence.
5) The Colliflower fence might be well be less troublesome if the aluminum were left bare without any coating at all.
6) You're going to need multiple "cube" blocks for different bevels and miter cuts; While these can easliy be made from pieces of 4 x 4 you need understand this requirement.
Despite all of the above, once you get it fitted tot he Kapex, the Colliflower vertical cube fence yields a singificant reduction of tear out on the back edge of the workpiece.
NOTE that I also purcahsed the Colliflower horizontal zero clearance insert unit (i.e. the one for the table) it fit properly and worked perfectly the fist time with no problems at all.
