Perhaps take a look at the web.xml file in $NXROOT\bopcfg\www\CATALINA_BASE\webapps\CAisd\WEB-INF
Make a backup copy before editting.
Look for the following and set the NO to YES:
<context-param>
<!--
set param to YES to "always" force a deflate on the compressed file before sending
to the browser. This may be necessary for certain application/browser relationships
that may not behave as expected.
-->
<param-name>forceDecompressOnDownload</param-name>
<param-value>NO</param-value>
</context-param>
Also the following and add docx and xlsx to the end of the list of extensions:
<context-param>
<!--
set param to comma separated list of extentsions that override browser behavior
in the context of forcing a Save-As dialog for specific extentsion types
-->
<param-name>save_as_dialog_ext</param-name>
<param-value>mp3,eml,doc,zip,gz,tar,xls,rtf,ppt,pps,msg,jpeg,jpg,png</param-value>
</context-param>
You will have to restart tomcat.