gcwsieve is now part of the mtsieve framework. See https://sourceforge.net/projects/mtsieve/. You can d/l Windows executables from there. There is no longer a need for two different sieving programs for gcwsieve. The mtsieve framework version is both faster than Geoff's (especially if your computer supports AVX). These is also a gcwsievecl version which you can use for sieving on a GPU.
BTW, the Cullen/Woodall sieve was originally part of MultiSieve, but Geoff rewrote it (and made it much faster) for gcwsieve. Since he no longer maintains it, I have taken it back and put many of his improvements into my version along with a few other tricks I have learned along the way.
All programs built on the mtsieve framework support multi-threading out of the box and the source is freely available to be built on any x86 platform. ARM support will be added in the future.
You can find the latest releases of srsieve, sr1sieve, and sr2sieve in this thread over at mersenneforum: https://www.mersenneforum.org/showthread.php?t=15833&page=26. I also maintain those programs. If you only need srsieve, then you can use srsieve2 from the mtsieve framework. srsieve2 is faster than srsieve for some bases and the same speed for others. Moving sr1sieve and sr2sieve to the framework is much more complicated. I don't know if or when that will ever be done.
If you have any questions or suggestions for enhancements to the framework or programs built upon it, ask or suggest.