It looks like keys with tilde ` and section § glyph are not working with OS X. I found a question on Official Apple Support Communities but there is no usable answers.
I highlighted a keys that does nothing.
I checked that on OS X Sierra on my MacBook 12" and on hackintosh with El Capitan 10.11.6. I do not have older version of Apple desktop OS to check that keys is physically working and not broken inside or on keyboard logic board.
I think that keys must be physically okay because this keyboard was into cardboard packaging as I bought it for a few years and now I found it and want to use with latest OS X.
Only workaround I found is open keyboard window and click that keys if I want to print them. But I'm a programmer and it's not really handy.