I am using snap and the Sentinel 1 toolbox on Mac and I think there is a problem with the path names. It says it can’t find the orbit files and they should be placed in .snap/auxdata\Orbits\Sentinel-1\POEORB. There is obviously a mix-up with the / used in unix or mac and \ used in windows.
Maybe that is not the only pathname which is set wrongly…
works now after changing the path in the .snap/etc/snap.auxdata.properties file.