A foam bag cushion forming system for forming foam bag cushions with a vertical side edge sealer that forms vertical side edge seals in the film material with the foam introduction preferably occurring after the downstream side seal is formed, before the upstream side edge seal is formed, and while the film material is being shifted from one to the other. An upper edge sealer operates to seal the upper end of the film material downstream from the dispenser and preferably also downstream from the side edge sealer. Through operation of the end and side edge sealers and the foam dispenser, a foam bag cushion chain is formed. A bag cushion moving and confinement assembly is positioned to receive the bag chain and features two elongated members defining a bag cushion confinement space between them. At least one of the elongated members supports or represents a bag cushion movement device (e.g., a conveyor) which acts to pull the preferably still interlinked bag cushions along the elongated members until the foam has had sufficient time to cure. In one embodiment, die impressions are supported on at least one of the two elongated members and extend into the foam material to form three dimensional foam cushions. The upper edge sealer is independently adjustable so as to vary bag cushion height while the moving device and side edge sealer can be controlled to form the desired bag length between side edge seal formation.