Classic/Universal Changing File Kind

[Dynamooo]

I have an application I downloaded that I know is a universal application. But when I unzipped it, it kind was listed as a txt file (god knows why :S). So I thought since Ive only just made the transfer from xp to os x in the last 6 months I could just rename the extension and off I go. But the application is now listed as Application (classic) and as a result wont execute. Im using OS X 10.5 with all updates. Any suggestions?

 

[swiftaw]

Would help to know what the application is

 

[Dynamooo]

The file is a rhino3d the mac version thats in development..

 

[Dynamooo]

Just a simple yes or no answer or an educated guess by anyone would be appreciated