The problem caused crashes in inflate function on MacOS. Probably due to mixing old and newer versions of functions. This function is used for PNG decompression, reading compressed containers and compressed HTTP requests. Probably also affected all zip file handling, too.
After we got a few quick workarounds in place for some customers on Thursday, we found on Friday the real cause, so the fixed built 220.127.116.11 could be made. The newer version of 9.4 is now uploaded on the website, so please switch to the newer version if you downloaded the older one already.
Thanks to all people reporting the bugs with crash reports.