It's a good idea to replace the filter when you replace the fuel lines, helps things flow easy. Good idea on keeping the spare carb. Zamas can be tricky to rebuild, in part because of the check valves in them. Since a carb kit usually costs $6-10, if you can get the carb for $20 or so, it is often smarter to just buy the carb. Of course, now you don't have to.
It is a very good idea to pour out all the gas and run the carb dry on any seasonally used piece of equipment to avoid just what you had to fix. Also, if you can, buy and use only non-ethanol fuel. You can locate non-ethanol stations at pure-gas.org.
You might want to inspect the clutch. Take an air compressor and blow out all the accumulated crud. Check to make sure all the springs are intact and hooked up. The interior of the clutch needs to freewheel separately from the drum that the chain is attached to, or the chain will turn all the time. If all that checks out, start the saw, let it warm up, then start turning down the idle screw until the chain stops turning. If your clutch is working right, the chain will stop before the saw dies.