Can't install Flat French Blue Skin

I see two skins folders - skins and tlbhost-skins.

When I try to choose a skin, I am offered all of those in skins, and one that's in tlbhost-skins.

I want to use Flat French Blue, which is in tlbhost-skins, and so isn't offered.

What do I do?

The "Flat French Blue" is the skin for Standalone True Launch Bar. If you are using the Standalone TLB, right-click the empty space of toolbar and select "Toolbar Properties". You can select skin on the "Skins" page (see the attached screenshot).

This is very puzzling.

You can see from the attachments that I have two folders containing skins. Why 2?

There are about 18 skins.

But only 13 or 14 are offered.

I have set up a Standalone TLB which has Flat French skin. But I am still not offered Flat French for the menus which hang off that. Why is this? I go into the menu, right click and then choose Customise menu... That's right is it?

What is the factor that enables a skin to be offered?

I must say that I had to fiddle about to get a Flat French, and it might have the wrong format. But I can't see it offered as a download from the website. So I can't re-install it.

Where is the version which is used by the Standalone Toolbar hiding? And where are the new one's that are now offered for the Standalone Toolbar itself, hiding?

Your message implies that French Flat can only be used on the standalone version. This can't be true, can it? Can it be used for non-Standalone menus?

Confused.

Even with Standalone TLB, the "Flat French Blue" skin does not change the menu appearance. This skin is only for toolbar.

About two folders:
skins - this folder is the main TLB skins folder. The skins from this folder can be selected in TLB Settings->Options->Skins

tlbhost-skins - skins for standalone toolbar. This is something like advanced background for toolbar.