I was able to obtain information from a helpful Eurail representative.  Making progress.

Thanks

For most day trains, reservations are optional and they should be €3 via e.g. tickets.oebb.at. Eurail overcharges. The night train is also best booked there (via ÖBB), but then by adding the Interrail/Eurail discount and then choosing "One-way tickets and day tickets”.
If you want more specific help, please mention the exact trains you want to book, with date and departure time.

rvdborgt

Thank you very much.  I was able to reserve seats on our trip from Budapest to Innsbruck and then from Innsbruck to Munich.  This was much easier to accomplish using your advice.  The reservations are downloaded and saved as pdf’s.  I was able to click seat reservations only.  I was not able to locate how to add the Global Eurail pass as a discount, but the seat reservations went through.

I was not able to locate a night train in the OBB system from Munich to Rome for early August.  Maybe that has to be 90 days out as well?

Thanks again,

Sean

rvdborgt,

Just a follow up.  I was able to find where to enter the global pass in discounts.  I was also able to set up our family group.  Was not able to find the nightjet though, but I’ll try 90 days out.

Thanks again.

Sean

@Sean Meade No need to try it again. There is no Nighjet running to Roma in August. It will go to Ancona instead (this one is already bookable).