EDIT: After further review, it appears that the bug discussed here can be avoided by simply unchecking "Enable Sticky Handles" at Menu/Options/Options/General. The bug arises when executing a Move or Duplicate command when a selected entity has a single sticky handle. The bug appears to be unrelated to the "Point Relative" command. 8/28/2019
V27 point relative simply does not work. I virtually only use it with the "From reference point" selected and "Reference point" checked.
As far as I can tell, the native Move and Duplicate commands have never worked reliably
well with the Point Relative command, at least not
in "from reference point" mode .
To verify, I tested your issue in versions 15,17, and 28, and got the same errors in all 3. Under some conditions, DC seems to ignore the original reference point and defer to a recent handle, wherever it may be. One of those "conditions" seems to occur when a numbered handle is visible in the selection.
I was unaware of or had forgotten this problem in the native commands, because I have always used macros to perform Moves and Duplications.
You can download the S, N, and M macros (select, duplicate, move) here in a single zip file: http://forum.designcadcommunity.com/index.php?topic=322.msg1404#msg1404
On my own systems I have reassigned the keyboard S, N, and M keys to activate the macros. The M and N macros are strictly From-Reference-Point move and duplicate. If I ever need to use a handle explicitly, I can always use the menu command, but that happens maybe once every few years, and never in 2D mode
The N and M macros work well with the Point Relative Command.
When doing a Move
using Point Relative
with "Reference point" checked, remember that after you click "OK" or press "Enter" you need to manually set a NEW Reference point (and then hit enter again if using the M or N macro). Otherwise the move will fail, because the virtual "from reference point" in the Move command (or M macro) is not necessarily the same as the "reference point" in the Point Relative command.
PS: The macros work by setting and using temporary handles in the background to allow the look and feel of of Reference Point Move and Duplicate while avoiding their inherent problems. They also allow a quick 4-point reference point move, as if 2 handles and two target points had been set (Not to be confused with the nonsensical 4-point move in the edit menu of the windows versions.) The macros also fixed the 180-degree-rotation bug that existed in all versions prior to v18.