Its very normal to have tightspots, but if you are using one of the original ramped rings from your crankset, they are very poorly made (the stamped steel ones anyways). Mine on my ghetto beater SS is ovalized to the point where I had to file the crank to fit it. If you order a good Surly steel CNC'd ring it will be about as perfect as possible and very resistant to bending/warping.
For the chain, you can add a KMC Half Link to the chain which is just as it sounds, a half a chainlink to replace a full link, so you can get that new chain to fit. It might make it too long as the chain wears, however. I usually use a PC1 BMX chain since they stretch very minimally in my experience.