Hmm, it appears that crombiecrunch *might* have taken it offline in favor of offering full installation services.  https://bitcointalk.org/index.php?topic=2285641.msg23197153#msg23197153

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STRAKS hashing algorithm is Lyra2REv2, which is only minable with CPU/GPUs. STRAKS will always support a decentralised asic resistant blockchain and will update the hashing algorithm if this one day should no longer be the case.  Note, however, due to the unique combination of SegWit, treasury reward, miner reward and Masternode payments, as of this writing, mining software and pools do not yet support STRAKS' coinbasetxn configuration. The only way to mine STRAKS, right now, is via the STRAKS' wallet.  Please refer to STRAKS’ github (https://github.com/straks/straks) and Discord if you require assistance.

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I have added the ability to include skein and lyra2z coins into json response.

Just need to include those extra params:
&factor[sk_hr]=xxx&sk=true&factor[sk_p]=xxx
&factor[l2z_hr]=xxx&l2z=true&factor[l2z_p]=xxx

You can also hack those coins into UI response using the same params. Add "&dataset=xxx" to save into tab for easy click access.
Please note that pressing calculate will remove those coins from response, as forms are not yet present.