Wikimedia site maintenance

Non-profit health information site needs help with the wiki. Our biggest problem right now is that mobile users can't access the site. I'm hoping it is just a broken extension. A recent update broke some extensions, but it had probably not been updated in years. So we need to fix those extensions. Also, we have no budget to speak of (although we did get donations from users to pay for this), so I will need to watch your work to begin to understand how wikis work, so I can do basic maintenance. I am not a newbie; I have some experience in html and extensive experience in CMSs like Joomla and WordPress. I won't bother you but I need some exposure. And were are hoping to find someone who will be available now and then for ongoing improvements and problem solving. Also need help installing and activating mediawiki extensions if we can afford it. A better search, a decent translation tool, and templates (which appear to be installed but not working). Also back to top if available. Site is helminthictherapywiki.org.