Only site collection administators can manage FBA users?

I have a user that needs to manage FBA users. Is it possible to give that access without making them a site collection administrator?
Not currently without modifying the FBA Pack.
This is exactly what I want to do. I want to allow only one user (who belongs to MemberGroup) per subsite to create/delete/modify other users, but only those who are in this subsite. I don't want him to be able to modify all FBA Users.
Can you please explain how to do it ? By modifying to code ? Or is this too complicated ?

Thanks in advance,

Nico.
In the pages themselves, there's some code to 'RequireSiteAdministrator' - just search for that and turn it off - then anybody would be able to access the pages. If you want to allow only users with certain permissions, check here:

http://stackoverflow.com/questions/7383859/set-permissions-on-sharepoint-application-pages
Thanks for your answer.
Sorry to be that bad, but when you talk about "pages", you mean FBA pages that are located in : C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\15\TEMPLATE\LAYOUTS\FBA ? Like UserDelete.aspx / UserEdit.aspx etc. ?

If i'm right, I will look through the link that you gave to me, and try to understand the way I should do this.

Thanks again :)

Nico.
Those are the ones - check the .cs files for the pages to see the code I'm talking about. (You'll have to download the source code from here:

https://sharepoint2013fba.codeplex.com/releases/view/120338

, as everything installed in SharePoint is already compiled).
Ok, I found RequireSiteAdministrator in the UserNew.aspx.cs . So if i change

get { return true; } for get { return false; }

All users will be able to create users, that's right ?

So If I want only certains users to access this page (and still don't want them to be Site Administrator)
But where the RequireSiteAdministrator is defined ? Maybe I can change its definition, to accept the OwnerGroup of the site, or even a personnalized group that I created ?

I hope I'm understandable, despite my poor english !

Excuse my bad knowledge of C# or code =/

And thanks for your precious time :)
Right, returning false from RequiresSiteAdministrator will allow anybody to access the page.

If later you want to restrict access to certain people, you would follow the info from here:
http://stackoverflow.com/questions/7383859/set-permissions-on-sharepoint-application-pages
(I haven't done this before, but I assume it should work fine)
Thanks for your answer.

I didn't write C# code before, so it will be hard for me. But I'll try and come back if it works someday :)
And btw if someone comes and has already done this before, or wanna try, any help would be appreciated.

Thanks,

Nico.
If you haven't coded before, we do provide custom development for the FBA Pack. Something like this would be covered by the hours in the support plan:

http://www.visigo.com/purchase.html
Just for being sure that I'm right, If I want to modify the RequireSiteAdministrator :

1) I download the SharePoint2013FBAPack.Source.1.3.4.zip
2) I extract it on my SharePoint server
3) I modify my UserNew.aspx.cs
4) I use the Deploy.ps1 (that is in the SharePoint2013FBAPack.Source.1.3.4 folder I extracted in 2) ) script on my SharePoint server ?

That's right ?

Regards.

Nico.

EDIT1 : Or should I modify (if i can) the .wsp file ? I can't find how to open/edit this file btw
No - You need to open the source code in Visual Studio. Make the change. Recompile. Package (Which will create a WSP). Use the Deploy.ps1 to deploy the .wsp file.
Oh ok ! Thank you very much for this perfect answer :) !

EDIT1 : And the final question : I guess this should be done on the SharePoint server of course ? Because I tried on my PC, but it cannot load SharePoint modules.