blay09, there's a problem with one of the object in your mod. Every time i placed Heavy Auto Sieve, the game always crashed. But, when i reaccesseed my saved data, the sieve was still on place and work as it was supposed to (it still crashed when I placed the block). Here's the log:

Edit: Please use pastebin for log files instead of embedding them directly.
http://pastebin.com/SSMFpEik

I hope you can fix this.

Experiencing the same issue with the regular Auto Sieve.

Edit: I went backwards and tried out previous versions up until 1.1.93 from here

Neither of the previous versions worked with FTB Presents Skyfactory 2.5 which may suggest that this is a compatibility issue with another mod?

It seems fine for me.
Maybe Mojang's server was down when the skin was requested and returned a blank array, which couldn't be converted to a Json object