I can create portals using the portal crystals and selected block, but then the portal doesn't actually work when I try to go thru it. the portal animation creates but i cant go thru. even when i used the same colour catalyst.

This is not a dimension mod; it's a transportation mod. The point is to make two portals out of the same block and color, which will allow you to travel between them. Creating only one portal without creating a second one for it to link to will not do anything. This mod does not add any new dimensions.