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I'm not familiar with the fragman package, but it seems that turning your code into a reprex (reproducible example) would be your best bet at getting a helpful response. This will ensure we're all looking at the same data and code. A guide for creating a reprex can be found here.
Also, any more information you can share about what's happening when it gets "stuck" would be helpful to include.
One more thought - I did a quick Google search and found that the fragman package includes a sample dataset. Are you able to run through the tutorial using the sample dataset without trouble?