menu order not according to RTL

You could just re-arrange the menu items in "Appearance > Menus"?

No re-arrange is needed as far as I know. I am using RTL too and GP works just fine with menu ordering. A menu from top to left in wordpress backend appears from right to left in RTL language. I saw the screenshot above. Logo is at right and menu is at left but in RTL, GP logo is in left and menu is at right by default. This problem is related to wordpress language settings. If a user wants RTL wordpress but in settings/general a LTR language is selected, the problem occures. The screenshot above shows that Lisa wants RTL wordpress but in backend language is LTR. If a RTL language is selected in settings/general, everything will be fine.

Example this is another site for the same company. http://a6871-tmp.s110.upress.link
Hebrew - logo float right, nav float left BUT the first menu is on the right
English - logo float left, nav float right BUT first menu is Beit Terezin and that sits on the left

http://prntscr.com/fxjh7a
As you can see the site is set to Hebrew (screen capture). this was already setup in the WordPress installation
Header (logo) is set to Right (which is correct)
Primary navigation is set to Float left (which is correct)
The first menu tap should be on the right. (which it isn't)

THis site will also have an English site just like the example above.

I already had a bilingual site in dari and pashto which are RTL languages and for testing purpose changed one language to Hebrew which is also RTL language. I did not see any difference at all and for three languages all of them were the same. Also I changed one language to Hebrew and another to English and tested them and It seems everything is fine for both RTL and LTR languages.
1- Float is right. For Hebrew it is RTL and for English it is LTR.
2- Text alignment is right. For Hebrew it is RTL and for English it is LTR.
3- First link or home button position is ight. For Hebrew it is on right and for English it is On left.
4- changing occures perfect from one language to another language. When I change language from Hebrew to English the menu goes to left and home page is the first one on left side. When I change language from English to Hebrew the menu goes to right and home page is the first one on right side.
So there are maybe two probabilities.
1- Check text alignment in appearance/customize/layout/primary navigation/navigation alignment.
2- If that is OK I think something is wrong with bilingual setup. If you are using a multilingual plugin once it will be good to check it is setup. I am using polylang and everthing is managed perfectly.
Hope it helps.

sharif Hi
when I installed WordPress I chose Hebrew as the system default.
In updates page, only Hebrew WordPress version appears = http://prntscr.com/fxmwiv
I have not even added multi language plugin yet as I first build the native language site
and only after upload WPML plugin to build the secondary language which will be English.
http://prntscr.com/fxmvri - see general settings > system language

This is my 10th multi language site so I do know what I am doing.
This is my first Hebrew site on GP - as a single language RTL site (not yet complicated by multi language plugin)

see site after I added a new menu. home should be on the right hand side
http://www.p8072-158-1962.s158.upress.link/

Please note that in mobile version the menu order is correct. 1 -home is top, 6 contact is bottom - as it should be.

link to site
http://www.p8072-158-1962.s158.upress.link/

Try adding this CSS:

.rtl.nav-float-left .main-navigation li {
    float: right;
}

I tried above css and it seems to solve the problem.

Awesome - is this a confirmed issue with all RTL instances?

No. Definitely No. I have tested GP with four different RTL languages and did not see such an issue. Even I tested Hebrew and everything was fine. When a menu is created in wordpress back end, we know it is from top to bottom in backend. In RTL that top to bottom menu appears from right to left accordingly in frontend.

Thanks guys. this fixed the issue.
I hope that when I come to do the English language site that it goes smoothly

thanks
Lisa

so sticky menu float left is being over ridden.
http://prntscr.com/fy0ahw
can you help me get the menu to float left on the sticky menu

Try this as your complete CSS instead:

.rtl.nav-float-left .main-navigation {
    text-align: left;
}

.rtl.nav-float-left .main-navigation li {
    direction: rtl;
    display: inline-block;
    float: none;
}

Thank you Tom, I was facing the same problem with with Floating left menu in an RTL website.