Just to keep everyone posted, the issue with about us/privacy and terms pages has been resolved. The instruction provided by support team worked.
I checked with my host provider and found that mod_rewrite was enabled for all my domains. Then I followed the rewrite instructions in the .htaccess file. The only string of commands I updated on the existing .htaccess file were the following:
RewriteRule ^index\.html?$ / [NC,R,L]
This resolved the problem for me on the IGallery Script. Most likely this will also work on other scripts if I face a similar problem.