Ran into same thing with a 1099-B imported from Fidelity with a capital gain transaction from GLD. It did not show any option for collectibles.
I ended up selecting the option that the sales fess/expenses were incorrect and typed at a $1 basis adjustment. This created a "Capital g/l adj" form in the forms view with a BE code. From this form I was able to select the Part III box titled "This is a sale of a collectible item (code C)." I also went back and did an override to uncheck the code B box "Form 1099-B reports an incorrect basis (code B)", and also unchecked the code E box "Amounts reported on Form 1099-B do not reflect sales fees/expenses that were charged (code E)".
Fortunately (or unfortunately for my pocketbook), this allowed the collectibles gains to flow into Sched D and its 28% Rate Gain Worksheet.
I noticed that Fidelity does a good job with tracking GLD fund monthly expenses proceeds, cost basis, and cap gain/loss. It also reported a properly reduced final basis on sale of GLD shares so you can pay even more taxes.
I had another brokerage with GLD and it never reported basis for any monthly GLD expenses. When I imported that 1099-B and went to review, it actually asked me if gains included collectibles, and on the individual transaction line, it gave me the full list of asset types to choose from, including collectibles. Also on sale of GLD shares, it did not decrease the basis from the original purchase price, so I had to do a manual cost basis override to pay more taxes.
