This applies to the 2.2 instance locally running at Texas A&M.
Today I tried to load a single MARC record through the Data Import UI. The binary marc record that I tried to load is attached, as well as the error log. The error log says that the record couldn't be loaded because of "Illegal unquoted character ((CTRL-CHAR, code 31))". I believe there are two issues with this: 1) If the error refers to \x31, that is not a control character. It is the Unicode character for a numeral 1. If it isn't referring to hex (perhaps octal?) then it would be very helpful if it specified. 2) The last iteration of the data import ui didn't require any characters to be escaped; it accepted binary MARC. Has something changed?
As you will be able to see, this is a vanilla record, very short and simple. There shouldn't be any problem loading it.