I can confirm some issues with creating a working case. The ERCOT model works when changing data for DA and SR. It does not solve within 12 hours when adding FR. Settings for FR were growth rate of 2% for energy and regulation. Energy up and down options were 0.3. Duration was set as zero, and evaluated as a combined market.
Are you using the full release version of DER-VET? Do the "Pre-defined" analyses on the splash page not work for you?
As for the ERCOT model, we are updating it to use monthly optimization windows. You are right that it takes a long time to solve when it uses yearly optimization windows, as in the first release. Thanks for bringing that up.