I don't know the real answer to this one but I do know of a bug when generating a Word document from RoboHelp. I know you are importing and from Fm but there could be a link. I have posted the bug below on Adobe's bug base and maybe it will give you a clue as to what to try.
Problem Description: If a table and the columns are measured in percentages, on generating printed documentation the column widths remain as a percentage but the table width gets converted to inches and not the same width that 100% would be. This results in table not fitting into page width. Measurements should be as defined in Rh.
Steps to Reproduce: Create a table with measurements set to percentages. Generate a printed document.
Actual Result: Table does not fit page width.
Expected Result: Table fits page width.
Any Workarounds: Manually fix in Word.
See www.grainge.org for RoboHelp and Authoring tips
Thank you, Peter. I was really hoping it was not a bug, but it makes the most sense unless there is another hidden piece of the puzzle.
FrameMaker 2017 build 2and RoboHelp 2017 build 2 - still a problem