Tifany C. Sort of! There isn't a way to directly do this, but there are some workarounds.
What you can do is take your Classic Gamma and attach it to the Gamma 5 agent chat ("Add a gamma" → "Edit a gamma").
Your gamma stays in Classic format, it isn't converted to Gamma 5 cards. But you can use the new agent to edit it.
If you want to redesign a classic Gamma into a Gamma 5 template, you can do that using the agent. The agent will read your classic gamma's content and rebuilds it as a new gamma on the template you pick; and the original is not changed.