I would not recommend to use CastXMR, use every other miner except this one. It is not open sourced and also it is not as trutable as Doktor83 with his SRBMiner.
Also ESET keeps block this web for me some something shady is there.
You better stick with classics like XMR-STAK (also our port XMR-AEON-STAK it is open sourced too on Github), XMRig and the new SRBMiner.
As many other users that can be find posting on Bitcointalk, I have been running Cast miner for 5/6 months without any issues. Or at least no more than while using Stak.
My rigs have been working fine running Cast, did not get any virus or malaware. Performance and reliability have generally been superior than using STAK, not mentioning Cast is a lot easier to configure.
The software is updated regularly and the dev respond to questions on its forum topic here at Bitcointalk.
Yesterday the dev of Cast released a new version 9.05, that works with Cryptonight Heavy,
It has, at least on my case and a few other users, some minor issues while using Vegas GPU, but run flawlessly at +900Hs on RX580 cards. Normally the dev of Cast sort issues out within few days, I would be surprised if it will not be the case also this time around.