There are a few ways to diagnose issues with the node pack. On launch the console should already provide enough information regarding potential issues, but there are a few other options:
There is now a setting in Comfy setting page to enable or disable debugging of the node pack:
If you go to /mtb/status (for instance http://localhost:3000/mtb/status), you will be presented with a page showing the node that successfuly loaded and the ones that failed