This IS the .htaccess contents from both the root folder where the modx install resides and also the same file exists in the ‘private’ folder:
# -FrontPage-
IndexIgnore .htaccess */.??* *~ *# */HEADER* */README* */_vti*
<Limit GET POST>
order deny,allow
deny from all
allow from all
</Limit>
<Limit PUT DELETE>
order deny,allow
deny from all
</Limit>
AuthName gregsbootcamp.co.uk
AuthUserFile /home/z02greg/public_html/_vti_pvt/service.pwd
AuthGroupFile /home/z02greg/public_html/_vti_pvt/service.grp
Do you have a file in the same folder called ht.access? That would then be the file supplied by the modx package.
The file you list looks to be from your hosting supplier.
Check the ht.access file to see what you would need to insert into the already existing .htaccess file.
Madeye