...Would be a function to force a specific sim to go to a lot.

To avoid E12, I have to greatly limit (to pretty much never) switching households temporarily, which is what I used to do if I wanted to make a given sim visit a given lot.

The MC has a function that will even cause a sim to move in, and also a function to force a sim to go home...but not one that will just force a sim to show up. It seems (though maybe it isn't) like just making a sim visit a lot would be less difficult of coding than the others.

Of course, one can always call the desired sim and invite them to come, but they don't always accept; and even when they do, the travel apparently is not given high priority as sometimes they accept and don't make it (and using Awesome's "whereis" command I see they ended up never leaving the venue they were at or essentially stopped along the way and decided to go elsewhere else....)

That may be realistic-- certainly the declining of invitations but also even the accepting but not showing up-- and it's a "cheat" to override it, but the mods we use allow for cheats and at least some of the time it has to do with a trapped error causing a sim to be reset and we just want the sim back....

Nraas>MC>Basic>Invite Over

Right, the only drawback to Invite Over is that you must have an active sim in the location that you want the inactive to go to. What we don't have is a "Go There" (as opposed to a "Come Here") command, but it sounds like that wasn't what was being asked for anyway,.

Invite Over sends the inactive to wherever your sim is. They can get lost along the way (routing issues, usually) but they don't get much of a chance to consider and refuse.

The only other times I've seen them not show up besides routing with that command is if their at work or their motives are dangerously low

When I said they don't get much of a chance to consider and refuse, I was being "cute." They are pushed to where your sim is. A subsequent push shouldn't interfere with that, other than life threateningly low motives as you said, but I've seen it happen (rarely). Probably an overly busy game engine causing routine things to get dropped in my case at those rare times.

Or it could be a trait they have I've seen Workaholics completely ignore the command when at work or close to their work hours.
Inappropriate sims seem to be the most difficult sometimes I've had to use the command 2 or 3 times and that with a world that only had 27 sims

I may have been working on a bad assumption, that "Invite Over" was like calling and inviting where they had the chance to refuse, as if inviting them by phone (and routing error or whatever it is, occasionally agree but still not show up). The word "Invite" may have misled me there. Maybe to avoid routing errors an option could be done that sends them by teleport? "Teleport here" or something?

When I've used "invite over" my sim often is informed the person invited is busy and call back in an hour .. or two hours (sometimes because they are at work) or they just don't feel like coming. And of course as mentioned above they accept the invitation and never show up due to whatever.
Depending upon your play style there is a work around I use. For Sims refusing, or not showing up (as long as it is not due to work) I use MC to make them active and teleport them where I want them. Again, that would depend upon play style. I play rotational so that works okay for my game.

@brappl - Wait, you get an "I'm busy" or don't feel like it response from MC's Invite Over? Not using a phone, I mean the actual MC command. I don't think I've ever seen that unless the sim really was at work at the time, and even then they still seem to manage to make their way over after their shift is finished. Maybe I've just been lucky all this time, but I've even gotten perfect strangers pulled over to where my sim is (or attempted if routing issues) using the command.

@igazor: I think brappl means when she uses "Invite Over" on the phone, not MC. Whenever I use MC to invite over, I get a notification in the top right-hand corner of the screen for each sim either saying that they'll be right over or that they're unable to. The messages in the middle of the screen about being busy and calling back later, are the standard EA ones when using the phone to invite over.