Trouble with titles over freeze frame on Final Cut Express - Help!

[bentramer]

I'm having trouble putting titles onto some freeze frame images on a Final Cut Express project. Every time I attempt to superimpose the text I get the following message: "Codec not found, display unavailable. Select a different codec using 'sequence settings' and close and reopen window to restore." I attempted this, but none of it made sense to me. Can anyone help with this? It's the very last piece of a long-in-progress project. My thanks in advance!