Neill, filming a movie on location in Turkey, worked with Williams on Bicentennial Man.
The movie was released in 1999 and after the New Zealand premiere, Williams, his then wife, Marsha Garces, and their children, Zelda and Cody, holidayed in New Zealand and stayed four nights at Blanket Bay, near Glenorchy.
In a statement yesterday, Neill described Williams as ''a loveable, kind man and completely unique''.
''He was one of the very few people you get to work with and know who had, without question, genius.
''Comedy, schtick simply poured out of him, unstoppable.
''But for all his ebullience - the man could fire up a room or a set like no other - you always felt there was something very tender and vulnerable about Robin.
''He was perhaps really only entirely happy with an audience.''
Outgoing Blanket Bay general manager Philip Jenkins remembered an ''incredibly talented man'' who brought joy to millions, and described his death as a ''great loss''.
The Williams family flew into Queenstown on December 23, 1999, on a Gulfstream 3 after the premiere of Bicentennial Man and went to Blanket Bay, where they stayed until December 27.
The resort, renowned for its privacy, had only just opened but, unlike many celebrities, Williams made no secret of where he would be staying.
Mr Jenkins said the Williams family were the first guests to stay at Blanket Bay and the actor spent a large amount of time mountain-biking and heli-biking.
''He was fantastic - great fun, a great guy, a really nice bloke with, as you would expect, a wonderful sense of humour.
''My children were the same age as his. They [the Williams children] were bored and wanted somebody to play with, so I brought my children down and they interacted.
''He ... gave us tickets [to Bicentennial Man], signed by him.
''He was a really nice man, they were a really nice family [and] we were very privileged to have them here.
''It's a great loss.''
When Williams was dropped at the airport by Neill, he told the ODT he had also flown to Milford Sound on Boxing Day and up the Dart Valley.
He was impressed by the late-summer sunsets in the area and thought Queenstown was ''great''.
''All the places I saw ... it's just wonderful.
''It would be easy to come back. It would be lovely.''
Where to get help
• Lifeline: 0800 543-354.
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• Samaritans: 0800 211-211/(04) 473-9739.
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• Youthline: 0800 376-633, free text 234 or email talk@youthline.co.nz.
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