Do TB2K and TBX compile?
Toolbar 2000. It is used as part of SpTBX (see below). TBX I'm afraid I don’t know - development stopped a few years ago, and I switched to SpTBX. I would recommend you do the same - it is actively developing / supported, and you probably will not come across such questions as this in a couple of years (I hope)!
(I know that the “update” was not what you asked, sorry, this is what I would recommend. I don’t like the situation when I use third-party code that is no longer supported, and I need to take on this task and update each version.)
Does anyone use TBX?
Most people do not use TBX these days - development has stopped. Instead, they use SpTBX , developed by Silverpoint Development. It used to be a patch for TBX (so you would have three levels: TB2K, followed by TBX, followed by SpTBX), but these days it is based on TB2K, so it consists of only two layers.
Installation instructions are easy to use , and its installer also installs TB2K.
SpTBX provides additional controls on top of those provided by TB2K, and also provides skin support. It comes with a skin editor if you want to create your own skins. Many of them come with I will never use in commercial software, but the Office 2003 and Office 2007 skins are excellent.

One SpTBX demo with Office 2007 Blue skin
Update from TBX: Most TBX components have direct analogies in the SpTBX library, and renaming them to DFM and the form file and opening the form will be a good start. (Or use GExperts.) Some properties and events have changed or gone, which is annoying. I found that I could generally figure out how to achieve the same thing quite easily - it took about a day to update a large application for me, but you won’t find it with a non-direct smooth transition.
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