The LED display should not react the same whether there is a dongle connected or not.
The #16 LED should blink with the 1s decimal point .
Make sure that the PIC is completely seated.
Make sure that the LED driver is completely seated.
Make sure that the 7 segment LEDs are completely seated.
Double check your solder joints again. <-- this is most likely your problem
If that does not work, post pictures of the front and back of the board to help us diagnose the problem.
update: oops, too slow.