Checkout menu position and href in cart module

-- url of the page with the problem -- : localhost
-- HikaShop version -- : 2.5.0
-- Joomla version -- : 3.4.3
-- PHP version -- : 5.5.12
-- Browser(s) name and version -- : Firefox 37.0.2

Hi,

I've Hikashop Checkout Joomla menu position (HikaShop » checkout), the alias of this menu position is "checkout" (it's top level menu item).
I've in Hikashop backend main config -> SEF url options -> Checkout SEF name: checkout

Now, in cart module (default Hikashop cart module) I have checkout button href which points to: example.com/checkout/checkout, but when I do main config -> SEF url options -> Checkout SEF name: [empty], then checkout url in cart module looks like this: example.com/checkout (as wanted).
If I disable Checkout menu position and in main config -> SEF url options -> Checkout SEF name: checkout, then in cart module href looks like this: example.com/component/hikashop/checkout/Itemid=

Is this correct behaviour? Shouldn't this be (if menu position assigned): example.com/checkout, no matter if Checkout SEF name is filled or not?

What's more, something bad happens with SEF while I'm on another Hikashop menu position (for example category): sometimes in cart module Checkout href looks like this: example.com/some-category-alias/category/checkout (depends where am I right now), for example if I'm on manufacturer assigned menu I got: example.com/some-manufacturer-alias/checkout

As there're are tons of options, please, ask me about some settings and I'll post print screens or info.

Best regards,
Chris