pg, I do have a single page HTML site designed but I am new to TT. Also I am using version 7 because the interface is more streamlined, made more sense and less confusing, IMO. 1st, you can have as many rows as you like, up and down that go across. Within the row you can have 1 to 4 columns or cells. If your using v6 take a look at the content tabs in the user guide. If you're using v7 it's much easier, I think. Just go to the content tab and click anywhere on your page, not header of footer. The right two boxes will turn from gray to black, row and cell. From there you can add, delete, change the number and layout of the rows and the columns/cells within the row.
Also take a look, if you have not, at this blog tutorial as the user guide is toast( ha, ha).
That's about all I can do with my limited knowledge. TT uses bootstrap as it's base kernel, which is great, take a quick look (google bootstrap) when you have time.
In the TT features section it does say Drop & Drag, but as far as I can see the Drop should be dropped. All I can do is drag borders around. Keep in mind, English is NOT their native language.