Thanks for your reply. My BTC have been in a paper wallet since 2014 & presumably I have been given BCH, BTG, BCD since then. I will only be bringing them online to sell them, so though they all have the same private key, it'll only be used to instantly sell them. Does that sound OK? Alternately, I may only sell the BTC & send the other coins back to new paper wallets....if you can do that? Can you keep Bitcoin Cash in a paper wallet?
You should split the coins. My knowledge in this are is limited but I'm certain you should start moving the BTC first (send them either to new wallet or exchange).
Reason for that is because you are going to import or sweep the private key into another wallets so it's better to secure the most valuable coin.
Think you should search in technical section of this forum (or open topic there) to get better support and be absolutely safe.