My Satsynch does not talk to MAC OS X Yosemite Version 10.10.4 and I am completely stuck. What can I do?
According to the info on the developer's website, you can install the application on Mac up to Mountain Lion. There is no information about the Yosemite version of Mac OS X. However, you can use available instructions posted on the developer's page to install the application.
Install instructions: https://satmap.com/mac-satsync-install