I'll give quick answers to your questions
1. Click
here for bandwidth calculation. I'm not sure how fast your internet connection is but you will need at least 160KB/s or 1.28Mbps to run a full 16 slot css server running at 66 tickrate. Now you can use less internet connection speed per server by either limiting the cvar values such as sv_maxrate and sv_maxupdaterate. If you have 10Mbps connection, you can host more than 10 servers since not all of your servers will be filled with people 24/7. Now if you have 100Mbps connection, don't worry about the internet speed.
2. I recommend tcadmin. It works nicely on windows os and it's a perfect game panel for windows server edidtion. There's other game panels such as serverdoc and you can use it for free but you it's not as good and pretty as tcadmin. You would have to pay around $15 monthly for tcadmin master server and web server license. Click
here to visit tcadmin website. Now if you don't need a game panel and just want it to be stay up 24/7, you can use a simple batch file. You can check out the tutorial on this website.
3. You don't have to worry too much about this. If you have multiple CPU processors and if you are running 32+ slot servers, you would want to set affinity to each server so that they don't cause lag on other servers when they change map.
4. Now this takes some time to explain.
I. Creating a User
a. Right click on "My Computer"
b. Click "Manage"
c. Stretch "Local Users and Groups"
d. Double Click "Users"
e. Right click on the white space and click "New User"
f. Uncheck "User must change password at next logon"
g. Check "User cannot change password"
h. Create a user
II. Creating a FTP Server
a. Click "Start" at the bottom left corner
b. Click "Run"
c. Type "inetmgr"
d. Strech all trees
e. Right Click on "FTP Sites"
e-1. Go to "New"
e-2. Click "FTP Site ..."
f. Click "Next"
g. Provide description (FTP server's name)
h. Select an IP address and specify it.
I. Specify its home directory (The highest folder in the system that can be accessible by this FTP server. Your root, C drive or D drive is the highest directory in the system)
J. After creation, right click on the FTP server.
K. Click "permission"
L. If the name of the user you want to give access to this FTP server is "reaper16", type this name into the text field.
M. Click "Check Name"
N. Confirm the permission and close the window
III. Connecting to a FTP server
a. If you have assigned 123.123.123.12 as the IP address of the FTP server, you can access it by typing
Code:
ftp://123.123.123.12
into windows internet explorer or any other viewers. You can even use a FTP manager to connect to it.