Dell UP2715 portrait mode not support with OS X Sierra?

Hi All

I was working this morning normally, reading sheet music in portrait (vertical) mode with my mac mini and my movie led 24 with loctek and Vesa, i am a Classical Guitar, my 24 Apple have a several problem: Shadows, apple not yet support this old monitor

I just got the legend of Dell 5K monitors The UP2715 K and arrives these afteernoon

I just installed it next to my mac pro tube and I just carried a tremendous snub or better crochet in my eye

By turning the dell to portrait mode, easily with its fantastic base, and enter in preferences of mac system <screens and see that the possibility of rotation does not appear to 180",360" etc neither pressing the keys + command, appear in the down the botton but not look nothing and in the Dell function botton aseeing that in the preferences of the Screen is turned on (Autorrotate) but the mac desktop does not rotate, neither deactivating this option of the Dell monitor, and returning to the preferences of mac os, never change

I can rótate phisically the monitor but mac preferences select directly Dell up2715 and not work in advanced mode

I took two things for granted: 1.- The monitor has a value of first manufacture of 2500 $ 2.-Sell by dell this monitor wonder for WINDOWS, leaving without support and if we read the very little information support we find in the Page of Dell.

The consequence PORTRAID MODE in the advertising photos of the monitor we can see how they sell this monitor adding the great characteristic of rotation to put the monitor completely vertical, without need of arms: (locktek, ergotech, etc.) all thanks to its Fabulous support stand, is put and removed with a single magnetic click, incredible !!! It's misleading advertising, I've stung !!!

There is no coherence what we are talking about here, in this professional range the 2 platforms should have the same support, very bad

By DELL

And the question: is it all the fault of dell? Is it Apple's fault?

I'm not going to get anything from Dell support, and I bet nobody in apple will explain to me that thanks to thunderbolt 3 and future development at image level of up to 8k, which is already immediate, they are going to occupy in a Next update of the system. To finish refining core image.

The situation is the following:

If there is no luck tomorrow with the support (I am in Spain) and some user of this forum reveals a tool of third parties, to be able to rotate 360º, I will be forced to return the monitor in a couple of days.

As we say in Spain: "Con todo el dolor de mi alma" (with all the pain of my soul...)

I feel a tremendous disappointment

Thanks in advance

Cuerdadeplatino