You might try performing a major cleanup on one of these
beasties in Word as a test, because the problems might reflect when
and how the table has been created, then edited over and over,
possibly by multiple inexperienced users.
I would copy a table into a New, blank Word doc, named with a
test file name you'll need later for importing to RH:
1. In the table, select merged cells and select Table >
Split Cells to eliminate them.
2. Select Table > Convert > Table to Text.
3. Select the entire table and click Ctrl+spacebar (to remove
all styles).
4. Select all content and reverse step 2 (Table > Convert
> Text to Table).
5. Format the table afresh (don't merge any cells in Word -
save that for RH after the import).
6. Save the Word file.
7. In RH, import the file, assign styles, and merge cells
where needed.
Good luck,
Leon