A bit of an odd one this.
I am reading NIV84 in Reading mode with 4 columns, and with my font and zoom settings, the top left verse is 1 Sam 11:13 and the bottom right one is 1 Sam 13:7, with footnotes visible.
I tried to select 1 Sam 12:23-25 to apply a highlight, so clicked and dragged from the beginning of v23 downwards.
However, the blue highlight stopped at the end of v23a ("...to pray for you") even though the drag action continued down to v25.
I then tried selecting just v24, but it would not select! In fact I am unable to select anything from v23b-25 "And I will teach you ... swept away". I click and drag over the area, but no highlight appears.
I can highlight ACROSS the area i.e. start dragging before v23b and finish from the beginning of 13v1ff, but if I stop dragging inside v23b-25, the highlight stops at the end of 23a as above.
Has anyone else found this kind of thing, or can reproduce it with the settings above? (XP Pro SP3)
Problem disappears when after exiting reading mode.
UPDATE: Definitely something odd going on.
I went back to reading mode, and that passage was fine, but the reference range displayed was different. So I set the active reference to 1 Sam 11:13 as before, but this time displayed text began at the beginning of that verse, not partway through as before. Now the unselectable range reappears, but it it seems related to screen area, not to reference. See below

UPDATE2: Definitely a screen area issue. I jumped to the next page in reading mode, and the same thing happened. It seems that I can't highlight past the first word gap which occurs after the halfway point on the text line that is level with the highest footnote on the page.
UPDATE3: Yep, Logos just bombed after trying it on a third screenful. Sorry no log file - logging is disabled.
Thanks
Richard