I've dealt with this issue several times for a customer,
firstly,?
secondly, they have an alternative URL for downloads if the first isn't downloading correctly. (I'm not gunna google that for you).?
thirdly, 10.6.2 seems to be the latest for TSW's, and I'm pretty sure that Sonos isn't supporting the Crestron TSW's for future updates.
Sonos is a huge []Dain in the butt with TSW's, I would recommend an iPad on the same VLAN/Subnet as the speakers, and a Sonos boost, tbh.
Good Luck,
Scott Baker