you might have to be more specific in your explanation. “I can only get a solid background”. Are you making the file a PDS file so that it has the alpha? What is your image sixe in comaprison to the screen size?
Yes! You can make the lower thirds in Photoshop but I usually make them completely in After Effects. These days, if you can do it in photoshop, you can probably do it in AE. Also, After effects has lots of cool plugins that just can’t be duplicated in photoshop without lots and lots of work.