Plugin breaking the site - Upfront/Spirit theme

I've been struggling with this for two weeks. Website breaks by either causing a fatal error or the pages are totally screwed up. I turn off all plugins, think I've found the culprit... get things going, it breaks again, turn off all plugins, the original culprit works fine now, but another plugin will cause conflict.

The main ones that seem to be effecting it is the inc-Support plugin. At one point I had couldn't access the website at all and had to turn off all plugins via php to even get in. It is an intermittent problem that I can't always duplicate, but today I can't get the site operating at all. Getting fatal errors (Fatal error: Maximum execution time of 30 seconds exceeded in /home1/kktwins/public_html/ask/wp-includes/functions.php on line 4678). I've deactivated the plugins that seem to be involved. I'm desperate because I'm supposed to be having some online activities tomorrow and I desperately need this working.