Would you kindly add a description of the symptoms and workaround to the Hugin FAQ at http://wiki.panotools.org/Hugin_FAQ
Frankly, this case ('&' in the user name) is quite unusual, although '&' in the path happens relatively frequently.
What do you mean with 'make needs updating'? Is there a better version of make for Windows that can be used / shipped with Hugin that you know of? Please be specific.