Yes, you can do this by using a wildcard. Before using the wildcard, a complete hostname must be specified. It is necessary for 301 (redirect) errors.
VirtualHost { Hostname = www.website.net, *.website.net ... }
Yes, use the following option for the VirtualHost section or in a .hiawatha configuration file inside that directory:
ShowIndex = yes
No. If you want to use a different startfile for a directory, use the StartFile option in a .hiawatha file in that directory.
Yes. Hiawatha automatically generates and serves GZip-encoded versions of static text-based files such as HTML, XML, CSS and JavaScript, according to the requesting browser's accepted encodings. Compressed versions of files are served from a cache, avoiding repeated CPU-intensive encoding on each request.
You are probably using PHP in FastCGI mode. When using FastCGI, Hiawatha doesn't check if the requested file exists, because the FastCGI daemon could be located on a remote server. A directory index is only shown if the requested file is not found, but this will never happen if the StartFile of that directory is a CGI script to be handled by a FastCGI daemon.
There are two solutions for this issue:
Yes, that is possible since version 6.9. The Windows package of Hiawatha contains a Cygwin tool to run Hiawatha as a Windows service. Read the included Installation.txt for more instructions.