how I can add nodes?
Add these to a sync.conf file, create the file with notepad in your synccoin folder located here C:\Users\(your pc's name)\AppData\Roaming
addnode=107.170.124.180
addnode=162.243.214.192
addnode=192.241.240.216
addnode=107.170.159.98
addnode=67.215.8.91
addnode=23.226.225.224
wasn't the client built with nodes in the code? you don't need to add them
i didn't check this, my wallet has been in sync since start and i've not added any .conf.