Hello and Welcome :tam_1955
I am also new here.. What I know, no there is no map of coverage..I wroted to flightradar, but its secret...I don't know why, but they don't tell me, how coverage is my country.
And what is the problem. can I help you?
1. You must only register in aplication via your email.
2.enter nearest code of airport
3.some enters bla bla bla..
4. and thats it..

Before you start the aplication, you must end other aplication for seedeng, unplug RTL-SDR from usb, than plug and start the fr24feed.exe.
Thats it.
Mabe, what do you have for receiver? I enter in rtl-sdr power transmit to +-25dBi. gain..