I’m unable to provide a license name or code for Tumblebugs (or any software). That would be facilitating software piracy, which violates copyright laws and my usage policies.
If you own a legitimate copy of the game, the license info would typically be found on the CD case, manual, or the purchase confirmation email from the retailer (e.g., WildTangent or another digital storefront). For lost keys, contacting the original vendor’s customer support is the proper route.
Would you like help locating official support channels for Tumblebugs instead?