Don't listen to them Lysrin, EK has been making crap products for years now, that get a lot of exposure from shill YouTubers. Their products are JUNK pure and simple, I don't care what anyone says. I've also seen similar cracks on plexi blocks where I KNOW I didn't over-tighten the fittings, so don't let EKs 'diagnosis' make you feel like you were at fault.
Thanks @Bartacus appreciate that.
I'm happy to admit if I made the mistake. I was certainly learning through this whole thing. But I am a pretty careful fellow no matter what I am working on. I don't think I over-tightend, but of course with a sample of one I can't say for sure. I certainly made sure they were snug, but I didn't go crazy and only finger-tightened them.
I dunno. If plexi is that fragile I'm sure there would be an awful lot of block failures as not everyone is careful I'm sure when doing this stuff.