Dear Anshita,
regarding the BSP CRM_SVY_SERVER you cannot make a specific Alias for your survey.
For Case 1):
As I said in my post before you have to talk to your security officer to check if you can expose your CRM to the internet. Then you have to get a firewall setting / reverse proxy to allow access from the Internet to the CRM System. Regarding the user/password please check my post before.
Case 2):
I would guess that on the PC where you try the mailto option there is no mail program like Outlook or Thunderbird installed. As you never know what is installed on any client I would not make use of this scenario when you're addressing Internet users.
I think we're at a point where I can't help anymore via the forum. If you can't fix it yourself with the available information please think about enganging me as an external consultant.
Best regards
Gregor