Yesterday, after some fight with Slic3r (I think it is an awesome slicer, but sometimes make strange decision on paths and infill) I try kisslicer, in particular I was very curious about the prime pillar feature. I almost use the default settings and the first “standard” (without pillar) print come out fantastic! The perimeters at 0.1mm are clean and regular. So I try the pillar feature (I want to use it in future with the dual color extruders) but the gcode, after the free movement from 0,0 to the center of the bed it starts printing from the pillar, but one single circle without a skirt and so small does not adhere week to the bed, also if I flag the skirt, this will be generated only around the object and not the pillar. So after missing the first layer of pillar it moves to make the skirt and the first layer of the object and everything went OK, the skirt allow priming of the head, but when the second layer of the pillar shall be printed the first was not in place so the wrong parts of the pillar detach from the bed and I have to stop the print. Someone have the same problem?
Sorry Stefano. I’ve not use pillar yet. Good to hear you’ve tried Kiss though!
Kiss has good gcode commenting so you could find the code for the first layer of the pillar and manually push up the flow rate, or use your host application to increase the flow rate while its doing layer 1 of the pillar.
Also try the forum. They are normally very helpful http://kisslicer.com/forum/
neeee Cura power 
Thanks @Tim_Rastall , the interface is not so good as Cura, but does everything it is needed. We are quite convinced to buy the Pro version to have benefits for multi head. I check the Gcode and the extrusion seems fine, but when you see the machine printing seems that nothing come out of the nozzle. It seems the effect of an early retraction without re-
priming. We have not so much time yesterday, so we will retry. Another solution it can be adding a sort of skirt in the prexif gcode, but I prefer that is the slicer to do it automatically.
Anyway the quality result is very superb.
@Bartlomiej_Ceglik 
I love Cura too, and we use it a lot, but s ome settings are not available and for example I’m not able to do the adjustable wrench in one piece featured on thingiverse. Cura generate too much strong support and the movable part does not detach from the body. Anyway I try all of the three slicers and I had not found my winner yet
@Stefano_Pavanello change in cura menu -> export -> open expert settings there is “fill amount(%)”, distance x/y and distance z tweak it
if you have problem in friction fit objects try change your nozzle size in software tab advanced -> machine -> nozzle size. if your parts are to loos make value smaller if they don’t fit make it bigger.
Thank you @Bartlomiej_Ceglik I will try. Have you ever tried to make a double extrusion print with cura? I’m testing all the software to understand which is the best for avoid oozing of the non active head. Cura seems way much better than Slic3r, but some strings and spots are present on the piece anyway, this is the reason I want to try the prime pillar of Kisslicer
Software isn’t going to do anything for oozing of a non active head. The only thing you can do is retract. All software is going to retract the same when you have the same settings. You’re trying to solve a problem in software, that has to be solved in the real world…
Reduce the hot end transition zone with a good fan on the fins of the nozzle, and retract until you stop oozing.
Understand @ThantiK , probably I have different other settings that confuse me on this aspect. I’m using the E3D hotend that had very short transition and very good cold end. My problem is not with retraction, but mainly with re-priming after retraction. If too much priming I have to much material, if too less I do not material when restarting. Obviously I have to made more test to find the magic number in between, but it seems to me that also depend on the time that a certain extruder remain in idle, more time means a slow oozing inside the head so at priming I will have too much material, if the idle time is low I have less inside oozing and the restart is with less material… I know this is a complex aspect to manage well with double head
@ThantiK the prime pillar feature in Kiss as a software solution to feeling with ooze. Like slic3r you can also set a ‘standby’ temperature for inactive nozzles to reduce ooze. Or am I missing your point?
@Stefano_Pavanello something to consider: kiss lets you add a custom Gcode for layer ‘n’ and also for extruder changes. So, you could add your own ‘prime pillar base’ code on layer 1 or set up a ‘dump’ hopper on your printer in a corner with a blade on an edge and send the active extruder to it before it starts its layer to prime it and then as it fast moves to start the layer, the blade on the edge of the hopper removes any dangling extrudiate. Does that make sense?
@Tim_Rastall you miss my point. Oozing is something that needs to be solved by meat-space things. Prime pillar and standby temperatures don’t help too much when your nozzle is heating up material too far up and pushing filament out. And like you’re pointing out, you can do things like adding dump hoppers, etc - all meat-space solutions. There’s only so much software can do, and the slicing softwares we use all pretty much have the same abilities (custom gcode on toolchange, etc)
@ThantiK Fair enough. I think I might do some of my own tests one I’ve got the new machine working (progress is being made btw, just too busy to post much)
Thank you all for the suggestion and ideas, it is very interesting for me because there are a lot to learn and now I’m quite starting to read raw gcode and visualize it to understand what can go wrong before start printing. I will have to do some dedicated test to evaluate the oozing when waiting, I have to try different temperature and retract/priming combination and idling time, it can be boring, but normally you learn a lot by these test. I understand that slicers can’t magically change physical problems, but I learn that whit the same machine, with different method to generate the gcode change everything. It can be an obvious discover, but for me was not so obvious when I start adventure in 3D printing and more when we decide to built one on our own It’s very interesting share thinking with you guys
Regarding 'N layer custom gcode I see the feature and I don’thave much time to test, but it’s very interesting, it gives you more power control over the code.