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See > http://support.apple.com/kb/HT3669 If it doesn't appear there, Apple doesn't provide drivers for the scanner. Also, there's an application you can use with the scanner > http://www.hamrick.com/vuescan/umax_powerlook_1100.html
Not sure. If you posted to the correct server forum, someone could tell you, since most people with MacBook Pros only have the client version, whose compatibility may differ from the server version.
Not to mention, if you find Windows driver, you can likely install an older vesion of Windows that will at least share it on your Mac.
There are several open source driver sources*.