What we need to do is to tell WS10 the following.
Treat the strings between the following tag pair:
<?xm-insertion_mark_start.*?>
<?xm-insertion_mark_end ?>
to appear as a series of strings without breaking into individual segments.
So the tag pair (or as separate entries) needs to be treated like embedded tags, such <bold> <italic> <xref> etc.
From WS10 Management > Linguistic Tool Setup > Filter Configurations
I tried to modify the parsing settings but nothing worked.
It seems when FTS Server is in effect, there filter settings are not read (for Studio File Types)...
In addition, without writing any rules for <?xm-insertion_mark_.?> and <?xm-deletion_mark.?>, WS10 recognizes there tags (insertion mark as fragment, deletion mark to be suppressed)