Shopping isn't going to take that long. They should do tourist things!
They should do tourist things. Lalita hasn't been to this planet in a while, and he didn't do very many tourist things while he was here. They should go look at famous landmarks and kiss in front of them!
There are shuttle tours available - circle the planet a few times, land at neat spots on the way, have the run thereof till takeoff. They can just sign up for one that takes a week and be back at the port before Harlequin is. But not by much! Hello again, Harlequin.
He finds a buyer - a museum on Earth who is willing to cover shipping in order to get their hands on one of humanity's first homegrown warp-capable ships. (The Harlequin continues to stubbornly refuse to fire up its own warp drive, so it'll need to be transported as cargo.)
He methodically goes through the ship taking out all the things that are his and packing them onto the Prometheus, since he has the chance. This mostly amounts to more clothes, and some other odds and ends. Then he says goodbye and sends it on.
Also, as he is cleaning it out, the Harlequin suffers another system failure and all its computer systems are completely scrambled; he has to format them back to factory settings. Oh, well, the museum wasn't buying it for the data.
And now Prometheus is ready to go.
Time to steal more fire from the gods.
Eventually the computer spits back confident reports on how to translate warp equations into local tongues, and on who fails to be above plagiarism, but Isabella has yet to decide whether to seed the plans among several of the planet's nations or just one. She doesn't want them to start fighting over it on the eve of post-scarcity.
"I'm tempted to distribute plans to three scientists from this northern country here," she says, pointing at a map of the planet. "It has the most currently Federation-friendly culture, and it could self-support building the drive. But there are candidates from here, and here," she points at two more. "And if I give it out to more than one political unit, they're having a race, whether they know it right away or not, and races can get heated."
"You could end up with a race even if you didn't mean to," he points out. "Once somebody knows it can be done, if they're smart enough to figure out how, they will. Whoever you drop it on, they're probably going to publish about it, and not everybody who reads them is going to be from the same culture."
"That's true. I'm not sure what that implies about where I should drop the plans, though."
"Hmmmm... the first one and the last one," he says. "You're right about those guys being Federation-friendly, and the last bunch has that 'historical neutrality' thing going for them; if there's going to be a race, having them in it might keep it low-key."
Isabella considers this suggestion, then nods, and narrows her scan to get an idea of the layout of the offices of the best candidate from the northern country. "Do you want to make one of the drops?"
The species on this planet is nocturnal, so she sets a timer for the earlier sunrise of the two time zones to remind her to start scanning for life signs in the narrow area in question so she can beam down unsupervised.
That leaves a couple hours to draw up the plans in that language, if she wants to get it done today. Out comes the paper and the pens. Blank paper costs, but not all that much - it's compact and easy to make and nonperishable.
He can! He is welcome to. They will get it done faster that way. This will leave time for distraction. Especially since the scientists at that particular physics lab like to put in a late morning, apparently.
Isabella has a procedure here. She doesn't want to be caught on security cameras. She could just beam the plans down, but it would be hard to get them precisely targeted. She has a nice concealing outfit and a mini-EMP to disable surveillance devices long enough to find someone's desk and plunk down her gifts.
"Oh, don't you just - I guess you can't target the beam that precisely," he says. "I can target the beam that precisely!"
"You can? You can land this," she says, holding up the plans, "on somebody's desk and we don't have to go down?"
She hands over the plans and gestures at the transporter pad, smiling back.
"And done," he says cheerfully. "Do we wait around to see what happens, or take off?"