Results now are slightly different from before. You were linking to some dubious sites with very poor user reputations - sites such as tqlkg.com and kqzyfj.com - but I don't see those any more. I don't know whether the Arqam WordPress plugin is causing any problems, but check that you have the latest version.
The most likely cause of a poor site rating now is probably links to other sites which are themselves Red or Yellow rated. Your site links to the site 'forms[dot]aweber[dot]com', which appears to have been compromised to serve up malware, and which is listed in hphosts as a phishing site. I suggest you remove any links to aweber[dot]com immediately, and after a few days check to see if your own site is still being blacklisted.
http://sitecheck.sucuri.net/results/muaythaischolar.com Site is clean of malware ...
http://quttera.com/detailed_report/muaythaischolar.com .... but has links to suspect sites.
Problems with the site forms[dot]aweber[dot]com and domain aweber[dot]com :
Google Safe Browsing diagnostic page for forms.aweber.com
Google Safe Browsing diagnostic page for aweber.com
https://www.siteadvisor.com/sites/forms.aweber.com See user reviews
https://www.mywot.com/en/scorecard/forms.aweber.com
http://hosts-file.net/?s=forms.aweber.com "Phishing site"
http://sitecheck.sucuri.net/results/forms.aweber.com "Site infected with malware"
Malware details : Malware entry: MW:HTA:7 .htaccess file probably modified
See http://blog.sucuri.net/2010/04/conditional-redirects-or-the-htaccess-malware.html
http://labs.sucuri.net/?blacklist=forms.aweber.com
http://labs.sucuri.net/?details=forms.aweber.com