Can't place guidelines in certain areas

[KOAN]

Hi All,

I've been having an issue with guidelines for awhile now across several Archicad updates (currently in 26 Solo) which is that I can't seem to place guidelines in certain areas sometimes.  What it looks like is that the guideline will just disappear as I drag it to the place I'm trying to drop it.  This happens both when I drag it from the edge of the screen and when I copy an existing guideline.

And to be clear, I can still use guidelines within the project, it just seems to happen in certain areas.  This is a Plan issue, haven't seen it in other view types.  Just curious if anyone has seen this and knows what's the cause.

Thanks!

[Barry West]

A single Teamwork user in our office is having this exact issue. It doesn't happen on any other instance of Archicad in our office, only the one computer.