I just installed ITF and discovered that Oasis Landing is not a world, per se. So I stared with one of my saved worlds (this may be part of the problem already), figuring that one must travel to OL through the time portal. The portal appeared, my sim was able to activate it, and the time traveler appeared (my sim had a nice chat and even made friends with him!). However, it seems that all my sim can do with the portal is activate it, deactivate it and place it in their inventory. What must they do to travel to the future in the dang thing?!

Oh, and one more thing. While my sim was conversing with the time traveler from the portal, a taxi pulled up to the house across the street and a time traveler doppleganger emerged and stood around on the sidewalk. Is that supposed to happen?

Have you picked up all five fuses that have appeared on your lot after arrival of Emmit the time traveler. It will apear as an opportunity, and after collecting and returning them, you will be able to time travel.

Does the Opportunity pop-up like a "normal" one, 'cause there was no indication that the sim had to find five fuses?

I had a mod incompatibility that caused this to happen in my world. I wish I could remember which one I had to take out to fix it. But this mod caused the opportunity to not pop up. I think it was something from the Naughty Sims asylum but I am not sure.

Thanks for the info, kewpie! I do use several of Shimrod's mods from Naughty Sims Asylum. I'll try removing them to see what happens, then add them back in to see if it's one of them.

Edit: It appears to have been Shimrod's "Peeping Tom" mod. I isolated the problem to this mod and when I removed it from my Mods folder, I was able to time travel! Woo-hoo!