When adding a batch to the NSG loader, the user clicks submit now to start the loader but nothing happens
This is more common in a sandbox environment but can also happen on a Live environment.
The batches can get stuck on the test or live system if the job doesn't run, so to resolve this go into Monitor NSG loader, then in the options choose Drop Job, and then click Recreate Job. This kick starts the loader and when you go back into the NSG loader form you will see that batch has now started to run.
https://communities.bentley.com/products/assetwise/exor/w/wiki/8656/how-to-load-an-od-file