Here is a quick list of differences between our two products.

Crystal Gantt	Crystal Gantt Pro
Allows you to visualize Tasks within a single Project in the Gantt.	Allows you to visualize Tasks across multiple Projects in the Gantt, by first defining a Program. Optionally use JQL filters to select tasks that make up a Program.
Gantt specific data (Start/End date, Progress, Sort Order, Indent Level) gets persisted in custom fields that need to be added to your Projects.	Gantt Specific data gets persisted in a database outside JIRA, so no need for adding custom fields.

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