shop in a folder; using https with languages problem - use subdomain for secondary languages?

[prestashopdave]

Hello

my prestashop is installed in

 

http://mydomain.com/prestashop

 

if I active https no problem, but with language i got page not found

 

https://mydomain.com/prestashop/language

 

 

must I to touche the .htaccess for this case ?

 

second question: it's possible have my main language in:

 

http://mydomain.com/prestashop

 

and the other languages in subdomains ?

 

http://fr.mydomain.com/prestashop

http://de.mydomain.com/prestashop

 

 

thanks