A release candidate for TWIN 1.03 (used for misSEQuel) can be downloaded at twin-1.03rc.tar.gz.
TWIN source is available for download at twin-1.02.tar.gz.
A binary can be downloaded at twin-1.02-bin.tar.gz.

The sdsl-lite source used for this binary can be downloaded at sdsl-lite.tar.gz.

MD5 sums: 
2a4f8fc7a5234c68482a29391a74c733  twin-1.03rc.tar.gz
9493159c831e5a9169da6162f19009ff  twin-1.02.tar.gz
83e05db384e47c1a00210afbe1da94cf  twin-1.02-bin.tar.gz
7a9237ab92136f4424bcf1ab92a1e225  sdsl-lite.tar.gz